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Dieting and Metabolic Damage
- Thread starter Tatyana
- Start date
just sayin thank for the bump; it's a good read - even the second time
Tatyana
Elite Mentor
http://www.thyroid.org/professionals/publications/statements/99_11_16_wilsons.html
ATA Public Health Statement
American Thyroid Association Statement on "Wilson's Syndrome"
Updated May 24, 2005
The American Thyroid Association (ATA) has developed the following response to requests from patients and physicians for information about "Wilson's syndrome". The ATA Public Health Committee and Council have reviewed the material presented on the "Wilson's syndrome" website, considered relevant studies from the medical literature, and offer the following advice.
Summary
"Wilson's syndrome" refers to the presence of common and nonspecific symptoms, relatively low body temperature, and normal levels of thyroid hormones in blood. Dr. E. Denis Wilson, who named the syndrome after himself, contends that it represents a form of thyroid hormone deficiency responsive to treatment with a special preparation of triiodothyronine (T3).
The ATA's thorough review of the biomedical literature has found no scientific evidence supporting the existence of "Wilson's syndrome." The ATA also has specific concerns about the following issues.
First, the proposed basis for this syndrome is inconsistent with well-known and widely-accepted facts about thyroid hormone production, metabolism, and action. T3 is one of the two natural thyroid hormones. Normally, it is mainly produced in target tissues outside of the thyroid gland from metabolism of thyroxine (T4). This production of T3 from T4 occurs in a highly regulated manner. This is one reason that T3 is not currently recommended for thyroid hormone treatment in most patients with thyroid hormone deficiency. T4 therapy allows T3 to be produced, as it is naturally, by the regulated metabolism of the administered T4 medication to T3.
Second, the diagnostic criteria for "Wilson's syndrome"--nonspecific symptoms and body temperature measurement--are imprecise.
Third, there is no scientific evidence that T3 therapy is better than a placebo would be for management of nonspecific symptoms, such as those that have been described as part of "Wilson's syndrome," in individuals with and normal thyroid hormone concentrations.
Fourth, T3 therapy results in wide fluctuations in T3 concentrations in blood and body tissues. This produces symptoms and cardiovascular complications in some patients, and is potentially dangerous.
Complete Review
The "Wilson's syndrome" website lists 37 symptoms as well as "others" that can occur as part of the condition. All of these symptoms do cause suffering, distress, and functional disability in millions of people. Some of these symptoms can, in fact, be due to true hypothyroidism. In hypothyroid patients, they are typically responsive to thyroid hormone therapy. Other problems, such as asthma, are not associated with thyroid hormone deficiency. Many of these symptoms are present from time to time in virtually everyone. In addition to hypothyroidism, they may be due to a variety of illnesses or life circumstances. In other words, they are nonspecific.
The "Wilson's syndrome" website states that Dr. Wilson named this concept after himself "because it had not been previously described." In fact, for more than a century, the same set of symptoms has been given different names and attributed to a variety of causes by others, including the syndromes of neurasthenia, chronic fatigue, fibromyalgia, multiple chemical sensitivity, chronic Ebstein Barr disease, and chronic candidiasis.
The frequency of complaints attributed to "Wilson's syndrome" has been recently reviewed (Barsky AJ, Borus JF. Functional somatic syndromes. Ann Intern Med 1999;130:910-21) At any time, more than 20% of adults report significant fatigue and 30% have current musculoskeletal symptoms. Furthermore, the typical adult has one of the symptoms every 4 to 6 days, and more than 80% of the general population has one of these symptoms during any 2 to 4 week period.
The advocates of "Wilson's syndrome" view the cause, diagnostic evaluation, and treatment of these symptoms very narrowly. Their viewpoint does not acknowledge that when these symptoms are persistent, they may be due to a number of different subacute and chronic medical conditions, psychological or social stress, or mood disorders, including depression and anxiety. Some of these symptoms may also simply be a part of life. "Wilson's syndrome" attributes them all to a biochemical theory, which is unsupported by laboratory or clinical research. It does not consider the impact of other potential illnesses and psychosocial factors on how we feel. In doing so, attributing one or more of these symptoms to "Wilson's syndrome" may delay recognition of treatable medical illnesses and potentially addressable life stresses.
The ATA has the following specific concerns about "Wilson's syndrome" and its recommended treatment.
The diagnosis of "Wilson's syndrome" is based on an incorrect definition of normal body temperature: that it is 98.6ºF. (Mackowiak, et al. JAMA 1992;268:1578-1580) measured oral temperature in 148 healthy persons. Average temperature varied throughout the day. At 8 AM, the average temperature was 97.6ºF with more than 50% of all the measurements less than 98.6ºF, and many less than 98.0ºF. This study concluded that "thirty-seven degrees centigrade (98.6ºF) should be abandoned as a concept relevant to clinical thermometry."
The prescription of T3 for "Wilson's syndrome" is inconsistent with normal physiology and represents a potential hazard. There is no question that T3 is an active, effective thyroid hormone. However, in most vital organs, much of the T3 is produced by removal of an iodine atom from T4 delivered by the blood to sites of thyroid hormone action. The extent of T4-to-T3 conversion varies from one organ to the other, but in some organs, like the brain and pituitary, this process provides most of the T3. Treatment with T3 produces an unnaturally large amount of T3 in some organs. This may be inappropriate, especially in times of illness or nutritional deficiency. Long-term T3 treatment may cause harm. Excessive T3 treatment can affect the heart and skeleton. These effects can be serious and even life-threatening.
The sole clinical evidence supporting T3 therapy offered by the "Wilson's syndrome" website is in the form of testimonials from people who feel better after taking T3. Evidence of this kind, based on anecdotal reports of an unblinded intervention is potentially erroneous. Such reports fail to take into account two well established facts. First, many people who suffer these symptoms, even for months, get better without any treatment. Second, as many as one-third of people with nonspecific symptoms have a so-called placebo response, i.e., they get better when they are given any treatment, even an inactive capsule or sugar pill. The appropriate way to assess a new treatment is to perform a clinical trial in which patients are randomly assigned to receive either the test drug or placebo. Furthermore, the response to treatment should be assessed in a double blind manner, keeping track of what gets better, what does not change, and what gets worse, with neither the patient nor the doctor knowing which treatment the patient is taking. The ATA has been unable to find any such studies of any treatment, including T3, for "Wilson's syndrome." The Wilson syndrome website reports only success stories. Responsible medical research into a new treatment keeps track of, and reports, not only successes, but also success rates, and how often there are inconclusive responses, failures, and side effects.
The term Wilson’s syndrome should not be confused with Wilson’s Disease. Wilson’s Disease is a well established and carefully studied rare metabolic disorder caused by excess accumulation of copper in the body.
Conclusion
The American Thyroid Association has found no scientific evidence supporting the existence of "Wilson's syndrome." The theory proposed to explain this condition is at odds with established facts about thyroid hormone. Diagnostic criteria for "Wilson's syndrome" are imprecise and could lead to misdiagnosis of many other conditions. The T3 therapy advocated for "Wilson's syndrome" has never been evaluated objectively in a properly designed scientific study. Furthermore, administration of T3 can produce abnormally high concentrations of T3 in the blood, subjecting patients to new symptoms and potentially harmful effects on the heart and bones.
The ATA supports efforts to learn more about the causes of somatic symptoms that affect many individuals, to test rigorously the idea that some as yet unidentified abnormality in thyroid hormone action might account for even a small subset of these symptoms, and to pursue properly designed clinical trials to assess the effectiveness of lifestyle, dietary, and pharmacological treatments for these common ailments. However, unsupported claims, such as those made for "Wilson's syndrome," do nothing to further these aims.
© 2006 American Thyroid Association. All rights reserved.
ATA Public Health Statement
American Thyroid Association Statement on "Wilson's Syndrome"
Updated May 24, 2005
The American Thyroid Association (ATA) has developed the following response to requests from patients and physicians for information about "Wilson's syndrome". The ATA Public Health Committee and Council have reviewed the material presented on the "Wilson's syndrome" website, considered relevant studies from the medical literature, and offer the following advice.
Summary
"Wilson's syndrome" refers to the presence of common and nonspecific symptoms, relatively low body temperature, and normal levels of thyroid hormones in blood. Dr. E. Denis Wilson, who named the syndrome after himself, contends that it represents a form of thyroid hormone deficiency responsive to treatment with a special preparation of triiodothyronine (T3).
The ATA's thorough review of the biomedical literature has found no scientific evidence supporting the existence of "Wilson's syndrome." The ATA also has specific concerns about the following issues.
First, the proposed basis for this syndrome is inconsistent with well-known and widely-accepted facts about thyroid hormone production, metabolism, and action. T3 is one of the two natural thyroid hormones. Normally, it is mainly produced in target tissues outside of the thyroid gland from metabolism of thyroxine (T4). This production of T3 from T4 occurs in a highly regulated manner. This is one reason that T3 is not currently recommended for thyroid hormone treatment in most patients with thyroid hormone deficiency. T4 therapy allows T3 to be produced, as it is naturally, by the regulated metabolism of the administered T4 medication to T3.
Second, the diagnostic criteria for "Wilson's syndrome"--nonspecific symptoms and body temperature measurement--are imprecise.
Third, there is no scientific evidence that T3 therapy is better than a placebo would be for management of nonspecific symptoms, such as those that have been described as part of "Wilson's syndrome," in individuals with and normal thyroid hormone concentrations.
Fourth, T3 therapy results in wide fluctuations in T3 concentrations in blood and body tissues. This produces symptoms and cardiovascular complications in some patients, and is potentially dangerous.
Complete Review
The "Wilson's syndrome" website lists 37 symptoms as well as "others" that can occur as part of the condition. All of these symptoms do cause suffering, distress, and functional disability in millions of people. Some of these symptoms can, in fact, be due to true hypothyroidism. In hypothyroid patients, they are typically responsive to thyroid hormone therapy. Other problems, such as asthma, are not associated with thyroid hormone deficiency. Many of these symptoms are present from time to time in virtually everyone. In addition to hypothyroidism, they may be due to a variety of illnesses or life circumstances. In other words, they are nonspecific.
The "Wilson's syndrome" website states that Dr. Wilson named this concept after himself "because it had not been previously described." In fact, for more than a century, the same set of symptoms has been given different names and attributed to a variety of causes by others, including the syndromes of neurasthenia, chronic fatigue, fibromyalgia, multiple chemical sensitivity, chronic Ebstein Barr disease, and chronic candidiasis.
The frequency of complaints attributed to "Wilson's syndrome" has been recently reviewed (Barsky AJ, Borus JF. Functional somatic syndromes. Ann Intern Med 1999;130:910-21) At any time, more than 20% of adults report significant fatigue and 30% have current musculoskeletal symptoms. Furthermore, the typical adult has one of the symptoms every 4 to 6 days, and more than 80% of the general population has one of these symptoms during any 2 to 4 week period.
The advocates of "Wilson's syndrome" view the cause, diagnostic evaluation, and treatment of these symptoms very narrowly. Their viewpoint does not acknowledge that when these symptoms are persistent, they may be due to a number of different subacute and chronic medical conditions, psychological or social stress, or mood disorders, including depression and anxiety. Some of these symptoms may also simply be a part of life. "Wilson's syndrome" attributes them all to a biochemical theory, which is unsupported by laboratory or clinical research. It does not consider the impact of other potential illnesses and psychosocial factors on how we feel. In doing so, attributing one or more of these symptoms to "Wilson's syndrome" may delay recognition of treatable medical illnesses and potentially addressable life stresses.
The ATA has the following specific concerns about "Wilson's syndrome" and its recommended treatment.
The diagnosis of "Wilson's syndrome" is based on an incorrect definition of normal body temperature: that it is 98.6ºF. (Mackowiak, et al. JAMA 1992;268:1578-1580) measured oral temperature in 148 healthy persons. Average temperature varied throughout the day. At 8 AM, the average temperature was 97.6ºF with more than 50% of all the measurements less than 98.6ºF, and many less than 98.0ºF. This study concluded that "thirty-seven degrees centigrade (98.6ºF) should be abandoned as a concept relevant to clinical thermometry."
The prescription of T3 for "Wilson's syndrome" is inconsistent with normal physiology and represents a potential hazard. There is no question that T3 is an active, effective thyroid hormone. However, in most vital organs, much of the T3 is produced by removal of an iodine atom from T4 delivered by the blood to sites of thyroid hormone action. The extent of T4-to-T3 conversion varies from one organ to the other, but in some organs, like the brain and pituitary, this process provides most of the T3. Treatment with T3 produces an unnaturally large amount of T3 in some organs. This may be inappropriate, especially in times of illness or nutritional deficiency. Long-term T3 treatment may cause harm. Excessive T3 treatment can affect the heart and skeleton. These effects can be serious and even life-threatening.
The sole clinical evidence supporting T3 therapy offered by the "Wilson's syndrome" website is in the form of testimonials from people who feel better after taking T3. Evidence of this kind, based on anecdotal reports of an unblinded intervention is potentially erroneous. Such reports fail to take into account two well established facts. First, many people who suffer these symptoms, even for months, get better without any treatment. Second, as many as one-third of people with nonspecific symptoms have a so-called placebo response, i.e., they get better when they are given any treatment, even an inactive capsule or sugar pill. The appropriate way to assess a new treatment is to perform a clinical trial in which patients are randomly assigned to receive either the test drug or placebo. Furthermore, the response to treatment should be assessed in a double blind manner, keeping track of what gets better, what does not change, and what gets worse, with neither the patient nor the doctor knowing which treatment the patient is taking. The ATA has been unable to find any such studies of any treatment, including T3, for "Wilson's syndrome." The Wilson syndrome website reports only success stories. Responsible medical research into a new treatment keeps track of, and reports, not only successes, but also success rates, and how often there are inconclusive responses, failures, and side effects.
The term Wilson’s syndrome should not be confused with Wilson’s Disease. Wilson’s Disease is a well established and carefully studied rare metabolic disorder caused by excess accumulation of copper in the body.
Conclusion
The American Thyroid Association has found no scientific evidence supporting the existence of "Wilson's syndrome." The theory proposed to explain this condition is at odds with established facts about thyroid hormone. Diagnostic criteria for "Wilson's syndrome" are imprecise and could lead to misdiagnosis of many other conditions. The T3 therapy advocated for "Wilson's syndrome" has never been evaluated objectively in a properly designed scientific study. Furthermore, administration of T3 can produce abnormally high concentrations of T3 in the blood, subjecting patients to new symptoms and potentially harmful effects on the heart and bones.
The ATA supports efforts to learn more about the causes of somatic symptoms that affect many individuals, to test rigorously the idea that some as yet unidentified abnormality in thyroid hormone action might account for even a small subset of these symptoms, and to pursue properly designed clinical trials to assess the effectiveness of lifestyle, dietary, and pharmacological treatments for these common ailments. However, unsupported claims, such as those made for "Wilson's syndrome," do nothing to further these aims.
© 2006 American Thyroid Association. All rights reserved.
Tatyana
Elite Mentor
A starvation diet does not mean the absence of food. It means cutting the total caloric intake to less than 50% of what the body requires.
To calculate what your body needs, you need to calculate your basal metabolic rate (BMR)as well as multiply this by the level of physical activity/training your are doing each week.
This is called the total daily energy expenditure (TDEE).
Many fear that going into starvation mode will drastically reduce their metabolic rate and cause them to hoard calories and gain weight instead of losing.
This is not borne out by the infamous Minnesota Semistarvation Study (1950), 36 young, healthy, psychologically normal men while restricting their caloric intake for 6 months. Their calories were restricted in various phases, but the least amount of calories they were allowed was 50% of the "normal" maintenance calories. Notice, this was dubbed a "semi" starvation diet.
Yes, their metabolic rates were significantly lowered -- to something like 40% below baseline. Yet at no point did the men stop losing fat until they hit 5% body fat at the end of the study.
Lyle McDonald explains it this way:
In general, it's true that metabolic rate tends to drop more with more excessive caloric deficits (and this is true whether the effect is from eating less or exercising more); as well, people vary in how hard or fast their bodies shut down. Women's bodies tend to shut down harder and faster.
But here's the thing: in no study I've ever seen has the drop in metabolic rate been sufficient to completely offset the caloric deficit. That is, say that cutting your calories by 50% per day leads to a reduction in the metabolic rate of 10%. Starvation mode you say. Well, yes. But you still have a 40% daily deficit.
And then he follows with the note about the Minnesota men still continuing to lose fat even thugh their metabolic rates had dropped to 40% below baseline. He says, further, that no study that he's aware of where people were put on strictly controlled diets failed to acknowledge weight or fat loss.
http://www.thefactsaboutfitness.com/research/lyle.htm
Did the Minnesota men suffer negative consequences from the experience. They most certainly did, and, interestingly, many of the same consequences that anorexics experience. You can read all about the various negative consequences at this site and the implications for EDs.
http://www.possibility.com/epowiki/Wiki.jsp?page=EffectsOfSe miStarvation
Another starvation study was done in England, at Cambridge University, to determine the different effects starvation had on lean people versus obese people. It's findings are quite relevant to our discussion. The entire study is found at http://www.unu.edu/unupress/food2/UID07E/uid07e11.htm.
Does starvation mode slow down the metabolism? No, and Yes.
In the first 2 days of starvation, there is a small absolute increase in BMR relative to values obtained from overnight fasting. Overnight fasting is what every one of us does during our sleeping hours.
So it is not true that going below recommended calories for one day is going to slow down your metabolism -- quite the contrary, it may speed it up just a little.
Does Starvation mode cause our bodies to catabilize (devour our muscles and other lean mass)? Yes and No.
Lean individuals lost great amounts of fat-free, lean tissue during starvation, but obese individuals lost much more fat tissue. Obese individuals have a mechanism that conserves lean mass and burns fat instead.
In the study, an example of a lean subject studied after death from starvation: it can be deduced that loss of body fat accounted for 28-36% of the weight loss and fat-free mass 64-72%.
In obese individuals, the proportion of energy derived from protein (Pcal%) is only 6% compared to 21% in the lean individual. More than half the weight loss in the obese is fat, whereas most of the weight loss in the lean individual is fat-free mass.
And the loss of lean mass is not as critical to the obese person as to the lean person simply because an obese person has more lean mass than a person of the same age and height but normal weight.
Grossly obese individuals (FORBES, 1987; JAMES et al., 1978) may have over 30% more fat-free mass than lean individuals of the same height. In the example shown in Figure 3, the obese individual weighting 140 kg has a fat-free mass that is 29% greater than the 70 kg man.
Obese individuals appear to have more muscle and bone than lean individuals, and these help support and move the excess body weight. Obese subjects have large vascular volumes and larger hearts, which are necessary to pump more blood around larger bodies, especially during weight-bearing activities. Obese individuals may also have visceromegaly (NAEYE and ROODE, 1970).
But when you think about it, doesn't that make fat storage sense? Why would our Maker create us with the ability to store fat if it couldn't sustain us and preserve our lean mass in cases of extreme want?
So the effects of a starvation diet upon a normal weight teen would be substantially more devastating than to me, a morbidly obese person.
Now, if the above gives anyone "permission" to undertake a starvation diet, I recommend remedial reading classes.
My opinion is, you should not go below your goal weight maintenance calories to lose weight, and you should do adequate research and dietary analysis to ensure you are getting the best nutrition you can for your calories.
If reducing your calorie intake to goal weight maintenance creates greater than 1000 calorie a day deficit, then I strongly suggest that you do a value half-way until you have lost some of your weight.
Now some advice for those unfortunate individuals who are suffering from EDs or who have foolishly ventured into starvation dieting. This comes from http://www.netwellness.org/question.cfm/28515.htm
Question:
Hi, I`m a RD. Have a client that is in the starvation mode. Know your are supposed to not change amount of calories consumed but help them to eat differently. Not sure what this means. Not had a client like this in past. Also, know it will take ~ 6 months for this client regain an appetite. Client states not hungry. I`m out in an area with not a lot of access to information. Hope you can help me to help them. God Bless
Answer:
Thank you for your question. Many people think that starving themselves will lead to fast weight loss. A starvation diet does not mean the absence of food. It means cutting the total caloric intake to less than 50% of what the body requires. The body responds by using its own reserves to provide energy, and these reserves are not just the body`s extra fat. Initially, glycogen stores are broken down for energy. Glycogen is the storage form of carbohydrate in our body. There is little glycogen available so this energy source is depleted during the first hours of starvation. When glycogen is used, water is released which is noticed as a drop in weight on the scale. These labile stores are quickly replenished when feeding is resumed which is noticed by an increase in weight.
The individual`s initial weight when starting a starvation diet will dictate to what extent fat is lost. Those individuals who are not obese (Body Mass Index (BMI) < 30) will tend to lose their lean body mass more easily and quickly than those who are obese (BMI > 30). It is dangerous for these smaller individuals to go on a starvation diet because the lean mass that is lost may come from organs such as the heart. In the 1970`s there were several deaths resulting from starvation-type diets. Death is a rare side effect, though.
The more common problem resulting from starvation-type diets is the resultant weight regain. Weight is typically regained because there has not been a change in the lifestyle that led to the original weight gain. When the starvation diet is ended, the individual returns to the same old habits. The scale will indicate the weight regain, but it will not identify the composition of the added weight. When weight is regained, it is fat. When fat replaces the muscle mass that was lost during starvation, the metabolic rate (the number of calories needed to maintain the current weight) is decreased. The frustrated individual typically initiates another starvation-type diet only to continue this cycle.
To help an individual break this cycle, begin with a diet history, and help the client make some small changes. The goal should be 4 - 6 small meals/snacks that result in a balanced intake. Also get the patient started exercising. Weight training will be important for rebuilding the lost muscle mass. Increasing muscle mass and increasing aerobic exercise will help increase the appetite appropriately. Don`t forget to help the client identify a realistic weight loss goal. That goal should never exceed 10% of initial weight in a six-month period. After six months, the client should try to maintain the loss for a few months before considering further weight loss.
To calculate what your body needs, you need to calculate your basal metabolic rate (BMR)as well as multiply this by the level of physical activity/training your are doing each week.
This is called the total daily energy expenditure (TDEE).
Many fear that going into starvation mode will drastically reduce their metabolic rate and cause them to hoard calories and gain weight instead of losing.
This is not borne out by the infamous Minnesota Semistarvation Study (1950), 36 young, healthy, psychologically normal men while restricting their caloric intake for 6 months. Their calories were restricted in various phases, but the least amount of calories they were allowed was 50% of the "normal" maintenance calories. Notice, this was dubbed a "semi" starvation diet.
Yes, their metabolic rates were significantly lowered -- to something like 40% below baseline. Yet at no point did the men stop losing fat until they hit 5% body fat at the end of the study.
Lyle McDonald explains it this way:
In general, it's true that metabolic rate tends to drop more with more excessive caloric deficits (and this is true whether the effect is from eating less or exercising more); as well, people vary in how hard or fast their bodies shut down. Women's bodies tend to shut down harder and faster.
But here's the thing: in no study I've ever seen has the drop in metabolic rate been sufficient to completely offset the caloric deficit. That is, say that cutting your calories by 50% per day leads to a reduction in the metabolic rate of 10%. Starvation mode you say. Well, yes. But you still have a 40% daily deficit.
And then he follows with the note about the Minnesota men still continuing to lose fat even thugh their metabolic rates had dropped to 40% below baseline. He says, further, that no study that he's aware of where people were put on strictly controlled diets failed to acknowledge weight or fat loss.
http://www.thefactsaboutfitness.com/research/lyle.htm
Did the Minnesota men suffer negative consequences from the experience. They most certainly did, and, interestingly, many of the same consequences that anorexics experience. You can read all about the various negative consequences at this site and the implications for EDs.
http://www.possibility.com/epowiki/Wiki.jsp?page=EffectsOfSe miStarvation
Another starvation study was done in England, at Cambridge University, to determine the different effects starvation had on lean people versus obese people. It's findings are quite relevant to our discussion. The entire study is found at http://www.unu.edu/unupress/food2/UID07E/uid07e11.htm.
Does starvation mode slow down the metabolism? No, and Yes.
In the first 2 days of starvation, there is a small absolute increase in BMR relative to values obtained from overnight fasting. Overnight fasting is what every one of us does during our sleeping hours.
So it is not true that going below recommended calories for one day is going to slow down your metabolism -- quite the contrary, it may speed it up just a little.
Does Starvation mode cause our bodies to catabilize (devour our muscles and other lean mass)? Yes and No.
Lean individuals lost great amounts of fat-free, lean tissue during starvation, but obese individuals lost much more fat tissue. Obese individuals have a mechanism that conserves lean mass and burns fat instead.
In the study, an example of a lean subject studied after death from starvation: it can be deduced that loss of body fat accounted for 28-36% of the weight loss and fat-free mass 64-72%.
In obese individuals, the proportion of energy derived from protein (Pcal%) is only 6% compared to 21% in the lean individual. More than half the weight loss in the obese is fat, whereas most of the weight loss in the lean individual is fat-free mass.
And the loss of lean mass is not as critical to the obese person as to the lean person simply because an obese person has more lean mass than a person of the same age and height but normal weight.
Grossly obese individuals (FORBES, 1987; JAMES et al., 1978) may have over 30% more fat-free mass than lean individuals of the same height. In the example shown in Figure 3, the obese individual weighting 140 kg has a fat-free mass that is 29% greater than the 70 kg man.
Obese individuals appear to have more muscle and bone than lean individuals, and these help support and move the excess body weight. Obese subjects have large vascular volumes and larger hearts, which are necessary to pump more blood around larger bodies, especially during weight-bearing activities. Obese individuals may also have visceromegaly (NAEYE and ROODE, 1970).
But when you think about it, doesn't that make fat storage sense? Why would our Maker create us with the ability to store fat if it couldn't sustain us and preserve our lean mass in cases of extreme want?
So the effects of a starvation diet upon a normal weight teen would be substantially more devastating than to me, a morbidly obese person.
Now, if the above gives anyone "permission" to undertake a starvation diet, I recommend remedial reading classes.
My opinion is, you should not go below your goal weight maintenance calories to lose weight, and you should do adequate research and dietary analysis to ensure you are getting the best nutrition you can for your calories.
If reducing your calorie intake to goal weight maintenance creates greater than 1000 calorie a day deficit, then I strongly suggest that you do a value half-way until you have lost some of your weight.
Now some advice for those unfortunate individuals who are suffering from EDs or who have foolishly ventured into starvation dieting. This comes from http://www.netwellness.org/question.cfm/28515.htm
Question:
Hi, I`m a RD. Have a client that is in the starvation mode. Know your are supposed to not change amount of calories consumed but help them to eat differently. Not sure what this means. Not had a client like this in past. Also, know it will take ~ 6 months for this client regain an appetite. Client states not hungry. I`m out in an area with not a lot of access to information. Hope you can help me to help them. God Bless
Answer:
Thank you for your question. Many people think that starving themselves will lead to fast weight loss. A starvation diet does not mean the absence of food. It means cutting the total caloric intake to less than 50% of what the body requires. The body responds by using its own reserves to provide energy, and these reserves are not just the body`s extra fat. Initially, glycogen stores are broken down for energy. Glycogen is the storage form of carbohydrate in our body. There is little glycogen available so this energy source is depleted during the first hours of starvation. When glycogen is used, water is released which is noticed as a drop in weight on the scale. These labile stores are quickly replenished when feeding is resumed which is noticed by an increase in weight.
The individual`s initial weight when starting a starvation diet will dictate to what extent fat is lost. Those individuals who are not obese (Body Mass Index (BMI) < 30) will tend to lose their lean body mass more easily and quickly than those who are obese (BMI > 30). It is dangerous for these smaller individuals to go on a starvation diet because the lean mass that is lost may come from organs such as the heart. In the 1970`s there were several deaths resulting from starvation-type diets. Death is a rare side effect, though.
The more common problem resulting from starvation-type diets is the resultant weight regain. Weight is typically regained because there has not been a change in the lifestyle that led to the original weight gain. When the starvation diet is ended, the individual returns to the same old habits. The scale will indicate the weight regain, but it will not identify the composition of the added weight. When weight is regained, it is fat. When fat replaces the muscle mass that was lost during starvation, the metabolic rate (the number of calories needed to maintain the current weight) is decreased. The frustrated individual typically initiates another starvation-type diet only to continue this cycle.
To help an individual break this cycle, begin with a diet history, and help the client make some small changes. The goal should be 4 - 6 small meals/snacks that result in a balanced intake. Also get the patient started exercising. Weight training will be important for rebuilding the lost muscle mass. Increasing muscle mass and increasing aerobic exercise will help increase the appetite appropriately. Don`t forget to help the client identify a realistic weight loss goal. That goal should never exceed 10% of initial weight in a six-month period. After six months, the client should try to maintain the loss for a few months before considering further weight loss.
Tatyana
Elite Mentor
Dieting and Metabolism
By WLR Dietitian
Juliette Kellow BSc RD
When we're bombarded with images of gorgeous celebrities who seem to lose weight in the time it takes us to eat a Danish pastry, it's no wonder we're often tempted to cut our already low calorie intakes in an effort to shift an extra pound or two each week.
But surprisingly, rather than helping us to reach our target weight more quickly, severely restricting calories actually prevents our bodies from burning unwanted fat stores effectively - and unfortunately, this means that weight loss slows down.
Why does a very low calorie intake slow down weight loss?
Quite simply, your body goes into 'starvation mode'. This mechanism, which is thought to have evolved as a defence against starvation, means the body becomes super efficient at making the most of the calories it does get from food and drink. The main way it does this is to protect its fat stores and instead use lean tissue or muscle to provide it with some of the calories it needs to keep functioning. This directly leads to a loss of muscle, which in turn lowers metabolic rate so that the body needs fewer calories to keep ticking over and weight loss slows down. Of course, this is the perfect solution if you're in a famine situation. But if you're trying to lose weight, it's going to do little to help you shift those unwanted pounds.
So how many calories should I have to prevent starvation mode?
Unfortunately, there's no single answer to this question. As everyone's metabolism varies in the first place, so too will the point when the body starts to use muscle to provide it with calories in a 'famine-type' situation. That's why WLR works out suitable calorie intakes for each member on an individual basis and never lets you opt to lose more than 2lb a week, which would require a severely restricted calorie intake. In other words, if you stick to the calorie intake recommended by WLR, you can be sure your body won't go into starvation mode.
As a general rule though, most nutrition experts recommend never going below 1,000-1,200 calories a day if you're dieting on your own. It's also worth bearing in mind that the body doesn't suddenly 'enter' and 'leave' starvation mode, like crossing the border from Devon into Cornwall. It's a gradual process - so you don't need to panic if you do go below your calorie intake very occasionally.
What's the link between muscle and metabolism?
The metabolic rate - the rate at which the body burns calories - is partly determined by the amount of muscle we have. In general, the more muscle we have, the higher our metabolic rate; the less muscle we have, the lower our metabolic rate. This explains why men, who have a high proportion of muscle, have a faster metabolism than women, and why a 20-year-old has a higher metabolism than a 70-year-old - again, they have more muscle.
Ultimately, muscle burns a lot more calories than fat so when we lose muscle, our metabolic rate drops and we burn fewer calories. In fact, research shows that the body loses a proportionately high amount of muscle with a very low calorie intake and this may considerably suppress metabolism by up to 45 percent.
This explains why it's crucial to do as much as you can to protect your metabolic rate, especially when you're dieting. And this means dieting sensibly with a suitable, rather than a very low calorie intake so that you lose fat rather than muscle.
Is there anything else I can do to stop losing muscle when I'm dieting?
As well as making sure you have sufficient calories to burn fat rather than muscle, it's also possible to build muscle, which in turn boosts metabolism. And the way to do this is, of course, to increase the amount of exercise you do. While aerobic activities such as jogging, swimming, fast walking and aerobic classes help to tone muscle and burn fat, strength or resistance training in particular will increase the amount of muscle you have in your body. And this is good news because for every extra 1lb of muscle you have, your body uses around an extra 50 calories a day! This means an extra 10lb of muscle will burn roughly an extra 500 calories a day without you doing anything - and that's a sufficient amount to lose 1lb in a week.
But doesn't your metabolism drop when you lose weight anyway?
Yes, your metabolic rate naturally slows down a little when you lose weight, but this isn't automatically because you've lost muscle. It's because when your body has less weight to carry around, it needs fewer calories. This means if you weighed 13st to start with and now weigh 9st, you need fewer calories to maintain your new weight than you did when you were heavier. Simply put, there's 4st less of you to carry up and down the stairs, into the bath, around the supermarket and to the bus stop - and because your body doesn't have to work as hard as it did in the past, it can survive on fewer calories! This is why you should regularly update your Goals and Results - as your weight drops, Weight Loss Resources will recalculate how many calories you need to keep losing weight at your chosen rate.
Will yo-yo dieting have damaged my metabolism permanently?
Fortunately not! The idea that yo-yo dieting permanently lowers your metabolism has been relegated to the archives. However, if you've frequently crash dieted and severely restricted your calorie intake without exercising, it's likely you'll have a lot less muscle now compared with the very first time you dieted. As a consequence, it's likely your metabolism will also be lower so that you need fewer calories to maintain your current weight. This is because when you follow a very low calorie diet, you lose muscle as well as fat (see above). But when the weight goes back on, you usually only regain fat. This means, your metabolic rate is likely to have dropped a little every time you've dieted, making it slightly harder each time for you to lose weight. The good news is you can increase the amount of muscle you have by increasing the amount of exercise you do. This in turn will rev up your metabolism so that you can lose weight one final time on a slightly higher calorie intake than you've perhaps been used to.
8 Ways to Speed Up Your Metabolism
By WLR Dietitian
Juliette Kellow BSc RD
Get active - it's a sure-fire way to increase the amount of muscle you have, which in turn will speed up your metabolism. Do a mixture of aerobic and resistance training for best results. And don't forget to be more active in your daily life too.
Eat little and often - there's evidence that eating small, regular meals throughout the day, rather than one or two large meals, may help to keep your metabolism ticking over. Surprisingly, around 10 percent of the calories we use each day go on digesting and absorbing food - so the more times you eat, the greater this effect is likely to be.
Eat plenty of protein-rich foods - research shows that around 25 percent of calories in a protein-rich meal may be burnt off. But make sure you choose low-fat protein foods such as lean meat, skinless chicken and low-fat dairy products.
Spice up meals - it's not an old wives tale after all! Spices like chilli are thought to raise metabolism by up to 50 percent for up to three hours after eating, due to increasing your heart rate. But before putting the local Indian takeaway on speed dial, work out which curries have the lowest calorie and fat content.
Swap you daily cuppa for green tea - there's evidence that it contains antioxidants that speed up metabolism.
Try a CLA supplement - more extensive studies need to be carried out before any definite conclusions can be drawn, but research has shown that conjugated linoleic acid (CLA) might increase muscle and therefore boost metabolism.
Chill out - research shows that being very cold can increase metabolism by up to 20 percent.
Have a sauna - being very hot is also thought to boost metabolism by about 20 percent (but check you don't have any underlying medical problems that mean you shouldn't go in saunas or steam rooms).
By WLR Dietitian
Juliette Kellow BSc RD
When we're bombarded with images of gorgeous celebrities who seem to lose weight in the time it takes us to eat a Danish pastry, it's no wonder we're often tempted to cut our already low calorie intakes in an effort to shift an extra pound or two each week.
But surprisingly, rather than helping us to reach our target weight more quickly, severely restricting calories actually prevents our bodies from burning unwanted fat stores effectively - and unfortunately, this means that weight loss slows down.
Why does a very low calorie intake slow down weight loss?
Quite simply, your body goes into 'starvation mode'. This mechanism, which is thought to have evolved as a defence against starvation, means the body becomes super efficient at making the most of the calories it does get from food and drink. The main way it does this is to protect its fat stores and instead use lean tissue or muscle to provide it with some of the calories it needs to keep functioning. This directly leads to a loss of muscle, which in turn lowers metabolic rate so that the body needs fewer calories to keep ticking over and weight loss slows down. Of course, this is the perfect solution if you're in a famine situation. But if you're trying to lose weight, it's going to do little to help you shift those unwanted pounds.
So how many calories should I have to prevent starvation mode?
Unfortunately, there's no single answer to this question. As everyone's metabolism varies in the first place, so too will the point when the body starts to use muscle to provide it with calories in a 'famine-type' situation. That's why WLR works out suitable calorie intakes for each member on an individual basis and never lets you opt to lose more than 2lb a week, which would require a severely restricted calorie intake. In other words, if you stick to the calorie intake recommended by WLR, you can be sure your body won't go into starvation mode.
As a general rule though, most nutrition experts recommend never going below 1,000-1,200 calories a day if you're dieting on your own. It's also worth bearing in mind that the body doesn't suddenly 'enter' and 'leave' starvation mode, like crossing the border from Devon into Cornwall. It's a gradual process - so you don't need to panic if you do go below your calorie intake very occasionally.
What's the link between muscle and metabolism?
The metabolic rate - the rate at which the body burns calories - is partly determined by the amount of muscle we have. In general, the more muscle we have, the higher our metabolic rate; the less muscle we have, the lower our metabolic rate. This explains why men, who have a high proportion of muscle, have a faster metabolism than women, and why a 20-year-old has a higher metabolism than a 70-year-old - again, they have more muscle.
Ultimately, muscle burns a lot more calories than fat so when we lose muscle, our metabolic rate drops and we burn fewer calories. In fact, research shows that the body loses a proportionately high amount of muscle with a very low calorie intake and this may considerably suppress metabolism by up to 45 percent.
This explains why it's crucial to do as much as you can to protect your metabolic rate, especially when you're dieting. And this means dieting sensibly with a suitable, rather than a very low calorie intake so that you lose fat rather than muscle.
Is there anything else I can do to stop losing muscle when I'm dieting?
As well as making sure you have sufficient calories to burn fat rather than muscle, it's also possible to build muscle, which in turn boosts metabolism. And the way to do this is, of course, to increase the amount of exercise you do. While aerobic activities such as jogging, swimming, fast walking and aerobic classes help to tone muscle and burn fat, strength or resistance training in particular will increase the amount of muscle you have in your body. And this is good news because for every extra 1lb of muscle you have, your body uses around an extra 50 calories a day! This means an extra 10lb of muscle will burn roughly an extra 500 calories a day without you doing anything - and that's a sufficient amount to lose 1lb in a week.
But doesn't your metabolism drop when you lose weight anyway?
Yes, your metabolic rate naturally slows down a little when you lose weight, but this isn't automatically because you've lost muscle. It's because when your body has less weight to carry around, it needs fewer calories. This means if you weighed 13st to start with and now weigh 9st, you need fewer calories to maintain your new weight than you did when you were heavier. Simply put, there's 4st less of you to carry up and down the stairs, into the bath, around the supermarket and to the bus stop - and because your body doesn't have to work as hard as it did in the past, it can survive on fewer calories! This is why you should regularly update your Goals and Results - as your weight drops, Weight Loss Resources will recalculate how many calories you need to keep losing weight at your chosen rate.
Will yo-yo dieting have damaged my metabolism permanently?
Fortunately not! The idea that yo-yo dieting permanently lowers your metabolism has been relegated to the archives. However, if you've frequently crash dieted and severely restricted your calorie intake without exercising, it's likely you'll have a lot less muscle now compared with the very first time you dieted. As a consequence, it's likely your metabolism will also be lower so that you need fewer calories to maintain your current weight. This is because when you follow a very low calorie diet, you lose muscle as well as fat (see above). But when the weight goes back on, you usually only regain fat. This means, your metabolic rate is likely to have dropped a little every time you've dieted, making it slightly harder each time for you to lose weight. The good news is you can increase the amount of muscle you have by increasing the amount of exercise you do. This in turn will rev up your metabolism so that you can lose weight one final time on a slightly higher calorie intake than you've perhaps been used to.
8 Ways to Speed Up Your Metabolism
By WLR Dietitian
Juliette Kellow BSc RD
Get active - it's a sure-fire way to increase the amount of muscle you have, which in turn will speed up your metabolism. Do a mixture of aerobic and resistance training for best results. And don't forget to be more active in your daily life too.
Eat little and often - there's evidence that eating small, regular meals throughout the day, rather than one or two large meals, may help to keep your metabolism ticking over. Surprisingly, around 10 percent of the calories we use each day go on digesting and absorbing food - so the more times you eat, the greater this effect is likely to be.
Eat plenty of protein-rich foods - research shows that around 25 percent of calories in a protein-rich meal may be burnt off. But make sure you choose low-fat protein foods such as lean meat, skinless chicken and low-fat dairy products.
Spice up meals - it's not an old wives tale after all! Spices like chilli are thought to raise metabolism by up to 50 percent for up to three hours after eating, due to increasing your heart rate. But before putting the local Indian takeaway on speed dial, work out which curries have the lowest calorie and fat content.
Swap you daily cuppa for green tea - there's evidence that it contains antioxidants that speed up metabolism.
Try a CLA supplement - more extensive studies need to be carried out before any definite conclusions can be drawn, but research has shown that conjugated linoleic acid (CLA) might increase muscle and therefore boost metabolism.
Chill out - research shows that being very cold can increase metabolism by up to 20 percent.
Have a sauna - being very hot is also thought to boost metabolism by about 20 percent (but check you don't have any underlying medical problems that mean you shouldn't go in saunas or steam rooms).
Tatyana
Elite Mentor
What is the minimum amount of calories that i have to eat every 2-3 hours to keep my metabolism up and prevent my body from going into starvation mode?
it varies from person to person...
from my experience, anyone who goes below 10 calories per lb of bodyweight will go into starvion mode (being normal, or slightly overweight... this doesn't apply to severely overweight people or obese people). the more meals you eat, the less likely you will go into starvation mode. but there's nothing set in stone. there are fortunate individuals (genetically blessed) who can eat 500 cals per day and burn purely fat and actually gain muscle (look at nigerians, they are mostly muscular and they don't have much food to eat... and they are extremely lean), and there are people who are very unlucky (bad genetics) who will not burn fat unless they calculate every single angle of their diet and training and do it flawlessly (takes years of educating one self and self experimentation).
i've noticed that you asked "what is the minimum"... never start a diet on "minimum". always start it on "maximum". if you start the diet and training on minimum nutrition, and maximum effort... where will you go from there if you plataeu?
you always hear the same thing over and over:
"i eat 500 cals per day, and i exercise for 3 hours daily... i've lost 23 lbs the first couple of weeks, but i can't lose weight anymore... why?"
you start out with maximum nutrition, and minimal effort... then you tip the scales slowly... you will have more options... and almost an endless route to fatloss and muscle gain.
it varies from person to person...
from my experience, anyone who goes below 10 calories per lb of bodyweight will go into starvion mode (being normal, or slightly overweight... this doesn't apply to severely overweight people or obese people). the more meals you eat, the less likely you will go into starvation mode. but there's nothing set in stone. there are fortunate individuals (genetically blessed) who can eat 500 cals per day and burn purely fat and actually gain muscle (look at nigerians, they are mostly muscular and they don't have much food to eat... and they are extremely lean), and there are people who are very unlucky (bad genetics) who will not burn fat unless they calculate every single angle of their diet and training and do it flawlessly (takes years of educating one self and self experimentation).
i've noticed that you asked "what is the minimum"... never start a diet on "minimum". always start it on "maximum". if you start the diet and training on minimum nutrition, and maximum effort... where will you go from there if you plataeu?
you always hear the same thing over and over:
"i eat 500 cals per day, and i exercise for 3 hours daily... i've lost 23 lbs the first couple of weeks, but i can't lose weight anymore... why?"
you start out with maximum nutrition, and minimal effort... then you tip the scales slowly... you will have more options... and almost an endless route to fatloss and muscle gain.
Tatyana
Elite Mentor
Determining the Maximum Dietary Deficit for Fat Loss
by Lyle McDonald
The Question
A long-standing question in my mind has been, “What is the optimal (or maximal) deficit for a fat loss diet?” Yes, I know I’m not the first to address the issue but I’ve always wondered if we couldn’t figure out exactly what an optimal deficit might be on a diet, rather than relying on annoying trial and error.
I’m sure readers are familiar with previous approaches but let’s run through them quickly. The simplest (read: totally retarded) method of setting calories on a diet is to give everyone some fixed amount. Usually women get 1200, men get 1500. How such an intake can magically be correct regardless of bodyweight or activity, I have no idea. But apparently a 300 lb man and a 150 lb man should both eat an identical amount and that amount is 1500 calories/day when they diet. Amazingly, in 2006, that kind of moronic stuff is still out there.
The second approach is along the lines of, “To lose one pound of fat per week, eat 500 calories/day less than your maintenance; to lose 2 pounds, eat 1000 calories less per day.” Simple math, although not entirely correct for a variety of reasons I don’t want to get into. I addressed problems with both approaches in the big Ketogenic Diet book.
In Bodyopus, Dan Duchaine (who was writing for lean folks, remember) recommended a maximum deficit of 20% below maintenance. Better, as this at least scales the deficit relative to maintenance. A big ass guy with a 4000 calorie maintenance gets a larger deficit (800 cal/day) than a small female with a 1700 calorie maintenance (340 cal/day). Of course, weekly fat/weight loss will be significantly different for the two, which seems to pass the reality check. Bigger males do lose more fat than smaller females. I regularly advocate this approach.
In the Ketogenic Diet book, I suggested setting a deficit based on current total bodyweight, since most people have trouble figuring out their true maintenance intake. Assuming an average maintenance intake of 14-16 cal/lb (you can use 15 cal/lb and split the middle), a 20% deficit yields ~11-13 cal/lb (and 10-12 cal/lb for dieting has been around in the bodybuilding world for at least a decade), which will then have to be adjusted based on real world results. Some people, for example, with low daily activity and shitty genetics, may have to go to 8 cal/lb AND do aerobics to lose fat effectively. Back when I was lifting twice/week and doing fuckall else activity, I had to do that. Now that I’m training 16-20 hours/week, I get to eat more when I diet. Hooray.
Now, empirically and based on research, it’s well established that…
a. fatter individuals lose more fat and less lean body mass (LBM) than leaner individuals; and
b. bigger individuals lose weight more quickly
By corollary, smaller/leaner individuals not only lose total weight/fat at a slower rate, they lose a greater proportion of LBM. The whole issue of calorie partitioning has been discussed to death in my various books, especially The Ultimate Diet 2.0.
It’s why those fat asses on “The Biggest Loser” can drop 8-10 lbs. a week, well at least for the first week (and some of that is certainly water, glycogen and clearing the shit out of their bowels), and someone at 12% bodyfat may struggle to drop one pound per week without sacrificing muscle.
And anybody who read the Rapid Fat Loss book notes that I sort of worked the above into the schema: based on starting bodyfat, fatter individuals end up with a larger deficit than leaner individuals. Leaner folks ended up maybe 40% below maintenance but fatter folks might have been as much as 75% below maintenance. But it was a rough back of the hand kind of calculation; it was more that I wanted protein intake set at a certain level and daily caloric intake sort of fell out of that. As it turns out, the feedback I’ve received tells me I was at least in the right ballpark: leaner folks aren’t losing LBM (as long as they set it up correctly) and fatter folks are dropping fat like crazy.
Now, some work on fasting had suggested a maximal rate of fat oxidation (you’d expect this value to be largest during total fasting, but the numbers never quite worked out how I wanted to express them. So I gave up on the question for a bit.
The basic question in my mind, and the one I’m going to address here is, “Based on an individuals’ current bodyfat/bodyweight level, do we know what their maximum rate of weekly fat loss can or will be?” Phrased differently, what’s the maximum deficit that they can run and spare lean body mass?
The Answer
So imagine my surprise when this little theoretical paper (note the journal title) showed up on my Pubcrawler last year (1). Titled, “A limit on the energy transfer rate from the human fat store in hypophagia”, it examined (from a somewhat simplified and theoretical way) exactly the question I gave above: what is the maximum rate at which the body can derive energy from fat stores to cover a diet induced deficit while sparing lean body mass.
It’s a nasty little paper, filled primarily with equations, explanations of those equations and some more equations to boot. Headache inducing to be sure. I’ll spare you the details. Based on a somewhat simplified analysis of what data exists (including the seminal Minnesota semi-starvation experiment), they conclude that the maximal rate at which fat stores can provide energy to the body is 290 +- 25 kj/kg which is approximately 31 kcal/lb of fat per day.
So, if you are carrying a mere 10 lbs. of fat, you can sustain a 310 cal/day deficit.
20 lbs. = 620 calories.
30 lbs. = 930 calories
You get the idea and this is not difficult math. Multiply your total fat mass in pounds by 31, that’s how much of a caloric deficit that fat mass can support on a daily basis.
One quick note: the above values are for dieting only and one of the simplifying assumptions in the paper was relatively ‘normal/moderate’ activity levels. The paper mentions specifically that the values above might be varied through pharmaceutical means (which target the rate limiting steps of fat energy transfer), or through high levels of activity. It even mentions bodybuilders specifically as a group that might exceed this value with a lot of training. For now, I’ll just focus on the diet end, I’ll come back to drugs and exercise afterwards.
So, the basic assertion of the paper is that, so long as the net daily deficit does not exceed what your fat stores can provide, you should spare lean body mass. And based on the small amount of research that they found, this seemed to be generally true (many studies find an initial rapid LBM loss but this is most likely glycogen and water and stuff, not muscle mass). By extension, if your daily caloric deficit exceeds the above, your body will have to mobilize LBM to cover the difference. So let’s look at an example.
Say we have a 180 lb male at 15% bodyfat. He has 27 lbs. of fat, and his maintenance calorie intake is 15 cal/lb or 2700 calories. With 27 lbs. of fat, he should be able to sustain a caloric deficit, from diet alone, of 27 lbs. fat * 31 cal/lb = 837 calories/day. So he could reduce his calories to 1863 (ha! 10 cal/lb) and shouldn’t lose any LBM at that level of intake. He should get a weekly fat loss of just over 1.5 lbs./week.
If the same 180 lb guy was at 10% bodyfat, only 18 lbs. of fat, he could only sustain a 558 calorie/day deficit (2150 cal/day or 12 cal/lb), he’s down to 1 pound per week. By the time he’s at 8%, he’s down to 14.5 lbs. of fat and a total deficit of 446 calories/day and about 2/3 a pound of fat loss/week. Oh yeah, if he were a fat shit at 30% bodyfat, that’s 54 lbs. of fat, he could sustain a deficit of over 1500 cal/day and lose over 3 pounds per week of pure lard; of course he’d only be eating 1300 cal/day. Again, the above all seem to roughly pass the reality check in terms of what we see in human dieters.
Now, one implication of the above is that, as a diet proceeds and your fat stores shrink, your net deficit has to decrease. Ok, step back, take a breath and read that again. More importantly, note my use of the word ‘net’ in the first sentence of that paragraph.
Now it’s going to get confusing.
At first glance, the above seems to be indicating that, as you get leaner, you’ll need to raise calories to compensate, so that the deficit isn’t as extreme. But that’s incorrect; it is saying that fat loss will need to slow (because the net deficit you can sustain will be smaller). By ‘net’ deficit, I mean the difference between your current maintenance requirements and your intake. This is important because, as you diet, your maintenance requirements go down due to the loss of bodymass along with the adaptive component of metabolic rate (due to insulin, leptin, ghrelin, peptide YY, etc). Let’s simplify this by looking at the math.
Our 180 lb man at 15% starts his diet. He has 27 lbs. of fat and can sustain a maximum deficit of 27 lbs. * 31 cal/lb = 837 calories. Assuming a maintenance of 15 cal/lb (2700), his starting calorie level will be 2700 cal - 837 calories = 1863 calories/day. He’ll be losing around 1.5 lb fat/week.
So now we check in 8 weeks later, he’s down 12 lbs., almost purely of fat (we’ll ignore any small LBM losses). His new numbers are 168 lbs. with 15 lbs. of fat = 9% bodyfat. Maximal sustainable deficit = 15 * 31 = 465 cal
Assuming his maintenance is still 15 cal/lb (not automatically a safe assumption), his maintenance requirements should now be 2520 calories. But the adaptive part of metabolic rate reduction has probably dropped him a good 10% below that. So let’s say his maintenance is 2250 cal/day or so. 2250 cal/day - 465 calories = 1785 calories. So, not much of a reduction from his previous 1863 calorie/day diet. Basically, the drop in his maintenance levels over the course of 8 weeks offsets the fact that he can’t sustain as much of a deficit and is now leaner. Of course, his fat loss has also slowed to just under a pound/week.
Now four weeks later, he’s dropped about 4 more pounds of fat. His new numbers are
164 lbs. with 11 lb of fat = 6.7% bodyfat. Maximal sustainable deficit = 11 * 31 = 341 cal
His maintenance will have dropped further, let’s say 14 cal/lb (people’s daily activity tends to go down due to the hormonal changes from extreme dieting) and a 15% adaptive reduction which brings him to 1951 calories/day. Reduce by 341 to get 1610 calories/day. He will need to reduce daily calories by a couple of hundred (from 1785/day to 1610/day) to achieve the maximum deficit but his fat loss will be down to 2/3rds pound per week.
Ok, step back for a second: the above calculations aren’t meant to be the holy word of god, there are a lot of estimates upon estimates being made, especially my guesses as to the changes in maintenance level and how big of an impact the adaptive component is having. The adaptive component is a big question mark with not enough data for my liking. Tracking morning body temperature gives a rough guideline: for every 1 degree drop in morning temperature below 97.8 degrees, your metabolism is suppressed by about 10%. This was more to illustrate what I meant by ‘net deficit’ with changes in both fat mass and maintenance requirements.
But, again, the above seems to scale roughly with reality. As people get leaner and leaner, fat loss slows drastically. To keep it moving, they have to either cut calories further or increase activity, both can cause muscle loss. Every bodybuilder who has had to move to 2 hours/day of aerobics to keep the fat coming off knows what I’m talking about. Drugs become more and more attractive as the myriad other systems start to fight back against you as well (on which note: will someone please get the folks working on intranasal leptin to hurry it up).
Drugs and exercise
As mentioned above, the paper I’m basing all of this nonsense on was looking at non-exercising dieting or fasting men, not folks who were training or taking drugs. And it mentioned specifically that both of those could potentially increase the maximum rate of fat mobilization value (above 31 cal/lb) without sacrificing lean body mass. Certainly, once again, this idea passes the reality check. Even the addition of the ephedrine/caffeine stack elevates fat loss while sparing muscle mass.
Clearly, exercise also has an impact. Even back in Bodyopus, Dan mentioned that only part of the total deficit (he used 20%) should come from diet, the other part should come from increased activity. This usually means aerobics, but some prefer to use high rep/short rest period weight training or interval training and there is some logic to picking one of the latter options. He suggested that men do better with 15% calorie deficit and 5% aerobics and women at 10% apiece.
Given the issues women have with lower bodyfat blood flow, and that aerobic activity can overcome some of the limitations that make lower bodyfat so stubborn, that makes a lot of sense. As well, women (because of their lower maintenance requirements), end up eating a tiny amount of food if they cut too much out of their diet. Increasing their net daily deficit via activity allows them to eat more and not starve to death on a daily basis.
Conclusion
In this article, I’ve been able to give dieters a starting point for the maximum sustainable deficit which can come from calorie restriction.
To summarize: simply determine how many pounds of fat you’re carrying. Then multiply that value by 31 calories. That’s how much you can potentially decrease your daily food intake. If you want to try to increase fat loss, any further increase in the deficit should either come from increased activity or compounds that either increase the mobilization or burning of fatty acids for fuel.
As well, as you get leaner/lighter, you will need to periodically recalculate your daily calories to take into account your diminishing fat mass and decreased maintenance requirements due to both decreased bodymass and the adaptive component of metabolic rate. An argument can also be made for saving increases in activity for later in the diet when your diet deficit has to be lower.
Please keep in mind, however, all of these theoretical calculations sort of pale to real world results. If you’re losing strength in the weight room like crazy, your deficit is too big regardless of what the math works out too, increase them until you stop hemorrhaging strength (and probably muscle). And even if you have to trial and error it a bit, the above should at least give you a starting point.
References
1. Alpert SS. A limit on the energy transfer rate from the human fat store in hypophagia. J Theor Biol. 2005 Mar 7;233(1):1-13.
by Lyle McDonald
The Question
A long-standing question in my mind has been, “What is the optimal (or maximal) deficit for a fat loss diet?” Yes, I know I’m not the first to address the issue but I’ve always wondered if we couldn’t figure out exactly what an optimal deficit might be on a diet, rather than relying on annoying trial and error.
I’m sure readers are familiar with previous approaches but let’s run through them quickly. The simplest (read: totally retarded) method of setting calories on a diet is to give everyone some fixed amount. Usually women get 1200, men get 1500. How such an intake can magically be correct regardless of bodyweight or activity, I have no idea. But apparently a 300 lb man and a 150 lb man should both eat an identical amount and that amount is 1500 calories/day when they diet. Amazingly, in 2006, that kind of moronic stuff is still out there.
The second approach is along the lines of, “To lose one pound of fat per week, eat 500 calories/day less than your maintenance; to lose 2 pounds, eat 1000 calories less per day.” Simple math, although not entirely correct for a variety of reasons I don’t want to get into. I addressed problems with both approaches in the big Ketogenic Diet book.
In Bodyopus, Dan Duchaine (who was writing for lean folks, remember) recommended a maximum deficit of 20% below maintenance. Better, as this at least scales the deficit relative to maintenance. A big ass guy with a 4000 calorie maintenance gets a larger deficit (800 cal/day) than a small female with a 1700 calorie maintenance (340 cal/day). Of course, weekly fat/weight loss will be significantly different for the two, which seems to pass the reality check. Bigger males do lose more fat than smaller females. I regularly advocate this approach.
In the Ketogenic Diet book, I suggested setting a deficit based on current total bodyweight, since most people have trouble figuring out their true maintenance intake. Assuming an average maintenance intake of 14-16 cal/lb (you can use 15 cal/lb and split the middle), a 20% deficit yields ~11-13 cal/lb (and 10-12 cal/lb for dieting has been around in the bodybuilding world for at least a decade), which will then have to be adjusted based on real world results. Some people, for example, with low daily activity and shitty genetics, may have to go to 8 cal/lb AND do aerobics to lose fat effectively. Back when I was lifting twice/week and doing fuckall else activity, I had to do that. Now that I’m training 16-20 hours/week, I get to eat more when I diet. Hooray.
Now, empirically and based on research, it’s well established that…
a. fatter individuals lose more fat and less lean body mass (LBM) than leaner individuals; and
b. bigger individuals lose weight more quickly
By corollary, smaller/leaner individuals not only lose total weight/fat at a slower rate, they lose a greater proportion of LBM. The whole issue of calorie partitioning has been discussed to death in my various books, especially The Ultimate Diet 2.0.
It’s why those fat asses on “The Biggest Loser” can drop 8-10 lbs. a week, well at least for the first week (and some of that is certainly water, glycogen and clearing the shit out of their bowels), and someone at 12% bodyfat may struggle to drop one pound per week without sacrificing muscle.
And anybody who read the Rapid Fat Loss book notes that I sort of worked the above into the schema: based on starting bodyfat, fatter individuals end up with a larger deficit than leaner individuals. Leaner folks ended up maybe 40% below maintenance but fatter folks might have been as much as 75% below maintenance. But it was a rough back of the hand kind of calculation; it was more that I wanted protein intake set at a certain level and daily caloric intake sort of fell out of that. As it turns out, the feedback I’ve received tells me I was at least in the right ballpark: leaner folks aren’t losing LBM (as long as they set it up correctly) and fatter folks are dropping fat like crazy.
Now, some work on fasting had suggested a maximal rate of fat oxidation (you’d expect this value to be largest during total fasting, but the numbers never quite worked out how I wanted to express them. So I gave up on the question for a bit.
The basic question in my mind, and the one I’m going to address here is, “Based on an individuals’ current bodyfat/bodyweight level, do we know what their maximum rate of weekly fat loss can or will be?” Phrased differently, what’s the maximum deficit that they can run and spare lean body mass?
The Answer
So imagine my surprise when this little theoretical paper (note the journal title) showed up on my Pubcrawler last year (1). Titled, “A limit on the energy transfer rate from the human fat store in hypophagia”, it examined (from a somewhat simplified and theoretical way) exactly the question I gave above: what is the maximum rate at which the body can derive energy from fat stores to cover a diet induced deficit while sparing lean body mass.
It’s a nasty little paper, filled primarily with equations, explanations of those equations and some more equations to boot. Headache inducing to be sure. I’ll spare you the details. Based on a somewhat simplified analysis of what data exists (including the seminal Minnesota semi-starvation experiment), they conclude that the maximal rate at which fat stores can provide energy to the body is 290 +- 25 kj/kg which is approximately 31 kcal/lb of fat per day.
So, if you are carrying a mere 10 lbs. of fat, you can sustain a 310 cal/day deficit.
20 lbs. = 620 calories.
30 lbs. = 930 calories
You get the idea and this is not difficult math. Multiply your total fat mass in pounds by 31, that’s how much of a caloric deficit that fat mass can support on a daily basis.
One quick note: the above values are for dieting only and one of the simplifying assumptions in the paper was relatively ‘normal/moderate’ activity levels. The paper mentions specifically that the values above might be varied through pharmaceutical means (which target the rate limiting steps of fat energy transfer), or through high levels of activity. It even mentions bodybuilders specifically as a group that might exceed this value with a lot of training. For now, I’ll just focus on the diet end, I’ll come back to drugs and exercise afterwards.
So, the basic assertion of the paper is that, so long as the net daily deficit does not exceed what your fat stores can provide, you should spare lean body mass. And based on the small amount of research that they found, this seemed to be generally true (many studies find an initial rapid LBM loss but this is most likely glycogen and water and stuff, not muscle mass). By extension, if your daily caloric deficit exceeds the above, your body will have to mobilize LBM to cover the difference. So let’s look at an example.
Say we have a 180 lb male at 15% bodyfat. He has 27 lbs. of fat, and his maintenance calorie intake is 15 cal/lb or 2700 calories. With 27 lbs. of fat, he should be able to sustain a caloric deficit, from diet alone, of 27 lbs. fat * 31 cal/lb = 837 calories/day. So he could reduce his calories to 1863 (ha! 10 cal/lb) and shouldn’t lose any LBM at that level of intake. He should get a weekly fat loss of just over 1.5 lbs./week.
If the same 180 lb guy was at 10% bodyfat, only 18 lbs. of fat, he could only sustain a 558 calorie/day deficit (2150 cal/day or 12 cal/lb), he’s down to 1 pound per week. By the time he’s at 8%, he’s down to 14.5 lbs. of fat and a total deficit of 446 calories/day and about 2/3 a pound of fat loss/week. Oh yeah, if he were a fat shit at 30% bodyfat, that’s 54 lbs. of fat, he could sustain a deficit of over 1500 cal/day and lose over 3 pounds per week of pure lard; of course he’d only be eating 1300 cal/day. Again, the above all seem to roughly pass the reality check in terms of what we see in human dieters.
Now, one implication of the above is that, as a diet proceeds and your fat stores shrink, your net deficit has to decrease. Ok, step back, take a breath and read that again. More importantly, note my use of the word ‘net’ in the first sentence of that paragraph.
Now it’s going to get confusing.
At first glance, the above seems to be indicating that, as you get leaner, you’ll need to raise calories to compensate, so that the deficit isn’t as extreme. But that’s incorrect; it is saying that fat loss will need to slow (because the net deficit you can sustain will be smaller). By ‘net’ deficit, I mean the difference between your current maintenance requirements and your intake. This is important because, as you diet, your maintenance requirements go down due to the loss of bodymass along with the adaptive component of metabolic rate (due to insulin, leptin, ghrelin, peptide YY, etc). Let’s simplify this by looking at the math.
Our 180 lb man at 15% starts his diet. He has 27 lbs. of fat and can sustain a maximum deficit of 27 lbs. * 31 cal/lb = 837 calories. Assuming a maintenance of 15 cal/lb (2700), his starting calorie level will be 2700 cal - 837 calories = 1863 calories/day. He’ll be losing around 1.5 lb fat/week.
So now we check in 8 weeks later, he’s down 12 lbs., almost purely of fat (we’ll ignore any small LBM losses). His new numbers are 168 lbs. with 15 lbs. of fat = 9% bodyfat. Maximal sustainable deficit = 15 * 31 = 465 cal
Assuming his maintenance is still 15 cal/lb (not automatically a safe assumption), his maintenance requirements should now be 2520 calories. But the adaptive part of metabolic rate reduction has probably dropped him a good 10% below that. So let’s say his maintenance is 2250 cal/day or so. 2250 cal/day - 465 calories = 1785 calories. So, not much of a reduction from his previous 1863 calorie/day diet. Basically, the drop in his maintenance levels over the course of 8 weeks offsets the fact that he can’t sustain as much of a deficit and is now leaner. Of course, his fat loss has also slowed to just under a pound/week.
Now four weeks later, he’s dropped about 4 more pounds of fat. His new numbers are
164 lbs. with 11 lb of fat = 6.7% bodyfat. Maximal sustainable deficit = 11 * 31 = 341 cal
His maintenance will have dropped further, let’s say 14 cal/lb (people’s daily activity tends to go down due to the hormonal changes from extreme dieting) and a 15% adaptive reduction which brings him to 1951 calories/day. Reduce by 341 to get 1610 calories/day. He will need to reduce daily calories by a couple of hundred (from 1785/day to 1610/day) to achieve the maximum deficit but his fat loss will be down to 2/3rds pound per week.
Ok, step back for a second: the above calculations aren’t meant to be the holy word of god, there are a lot of estimates upon estimates being made, especially my guesses as to the changes in maintenance level and how big of an impact the adaptive component is having. The adaptive component is a big question mark with not enough data for my liking. Tracking morning body temperature gives a rough guideline: for every 1 degree drop in morning temperature below 97.8 degrees, your metabolism is suppressed by about 10%. This was more to illustrate what I meant by ‘net deficit’ with changes in both fat mass and maintenance requirements.
But, again, the above seems to scale roughly with reality. As people get leaner and leaner, fat loss slows drastically. To keep it moving, they have to either cut calories further or increase activity, both can cause muscle loss. Every bodybuilder who has had to move to 2 hours/day of aerobics to keep the fat coming off knows what I’m talking about. Drugs become more and more attractive as the myriad other systems start to fight back against you as well (on which note: will someone please get the folks working on intranasal leptin to hurry it up).
Drugs and exercise
As mentioned above, the paper I’m basing all of this nonsense on was looking at non-exercising dieting or fasting men, not folks who were training or taking drugs. And it mentioned specifically that both of those could potentially increase the maximum rate of fat mobilization value (above 31 cal/lb) without sacrificing lean body mass. Certainly, once again, this idea passes the reality check. Even the addition of the ephedrine/caffeine stack elevates fat loss while sparing muscle mass.
Clearly, exercise also has an impact. Even back in Bodyopus, Dan mentioned that only part of the total deficit (he used 20%) should come from diet, the other part should come from increased activity. This usually means aerobics, but some prefer to use high rep/short rest period weight training or interval training and there is some logic to picking one of the latter options. He suggested that men do better with 15% calorie deficit and 5% aerobics and women at 10% apiece.
Given the issues women have with lower bodyfat blood flow, and that aerobic activity can overcome some of the limitations that make lower bodyfat so stubborn, that makes a lot of sense. As well, women (because of their lower maintenance requirements), end up eating a tiny amount of food if they cut too much out of their diet. Increasing their net daily deficit via activity allows them to eat more and not starve to death on a daily basis.
Conclusion
In this article, I’ve been able to give dieters a starting point for the maximum sustainable deficit which can come from calorie restriction.
To summarize: simply determine how many pounds of fat you’re carrying. Then multiply that value by 31 calories. That’s how much you can potentially decrease your daily food intake. If you want to try to increase fat loss, any further increase in the deficit should either come from increased activity or compounds that either increase the mobilization or burning of fatty acids for fuel.
As well, as you get leaner/lighter, you will need to periodically recalculate your daily calories to take into account your diminishing fat mass and decreased maintenance requirements due to both decreased bodymass and the adaptive component of metabolic rate. An argument can also be made for saving increases in activity for later in the diet when your diet deficit has to be lower.
Please keep in mind, however, all of these theoretical calculations sort of pale to real world results. If you’re losing strength in the weight room like crazy, your deficit is too big regardless of what the math works out too, increase them until you stop hemorrhaging strength (and probably muscle). And even if you have to trial and error it a bit, the above should at least give you a starting point.
References
1. Alpert SS. A limit on the energy transfer rate from the human fat store in hypophagia. J Theor Biol. 2005 Mar 7;233(1):1-13.
vixensghost
New member
Wow.
There are several ladies around here who could REAAAAALY benefit from this entire thread IF they take the time and read it!
There are several ladies around here who could REAAAAALY benefit from this entire thread IF they take the time and read it!
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