caloric deficit model, ketonic, and high-carb

[virtualcyber]

My question is about ketonic diet -- my question gets a bit lengthy, so please bear with me. In brief, my question is: why does it work?

We know that if body metabolizes greater amount of calories than the calories it effectively consumes, we lose weight. It seems to me, given the preceding, t-factor diet (also known as high-carb) diet does not make any sense. The theory goes that (1) the enemy of maintaining lean body is intake of fat (2) and that any moderate over-consumption of carbs are okay. It seems to me that if one overeats carbs, then it results in suppression of fat burning process (via insulin production) -- which means you will keep the fat you consume (even if it is in the range of 40 grams / day). Again, the bottom line seems to be that one has to eat less than one consumes.

If one follows that reasoning, ketonic diet should not be effective either. Again, for the body to burn fat, the intake of calories should be lower than the amount it metabolizes. So, what difference does it make whether the body learns to burn fat rather than carb when it is in the ketosis? If you eat 200 grams of fat, then, whatever calories that do not come from the consumed amount must come from body fat. But this is not much different than high-carb diet with low calories.

So, does anyone know why ketonic diet should work?

I will be grateful for any enlightenment.


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P. S.

What matters to me is _not_ whether I am heavy or light, but the ratio of muscle to body fat. So, to me, the question is: what kind of diet will promote greater muscle retention (or growth) and not as much for fat cells?

Assuming that ketonic diet works, then, is the logic here that the diet "fools" the body into not "eating" the muscle? This does not make that much sense to me -- because when the body goes into caloric deficit mode, it should try to eliminate any cells that are inefficient. That seem to be muscle cells, not fat cells.

 

[Par Deus]

Ketogenic diets work because you eat less on them because yummy things like steak, bacon, and cheese get tiresome after having it for 10 straight meals.

CKD's and TKD's work particularly well because of the carb-up/refeed.

 

[Dryloch]

Ketogenic type diet works partly because when you are in this state you are burning your fat for energy. The main two things you can burn for energy are sugar or fat. Your body breaks down fat into those ketones and your body uses em for energy. However when you are on that type diet you also lose ketones in your breath and in your urine etc. In other words you get rid of fat without having to use it for energy. That is why this diet is so succesful for many people. If you want the true easy to understand scientific info read Protein Power or Protein Power Lifeplan by Drs. Michael and Mary Eades. Both books are excellent especially the Lifeplan one.
If you don't eat much sugar your body has no choice but to burn fat. If you make sure and get a good amount of protein and excercise while dieting you won't lose much muscle.

 

[plornive]

I have read 3 books on ketogenic dieting: BodyOpus, the Anabolic Diet, and the ketogenic diet (lyle mcdonald). It has been found that the MAXIMUM # of calories lost through ketone excretion is 100 calories per day. Furthermore, ketones only supply the body with a SMALL percentage of energy once the body has adapted for the short term. This means that, while ketones only have 4.5 calories (1 ketone comes from 1 g of fat), it does not mean that for every gram of fat consumed, 4.5 calories are lost. It is simply not the case. Free fatty acids are used by the muscles more than ketones are after only two days on a ketogenic diet. This means that, aside from the approximately 200 calories lost due to inefficiency per day at max, the diet is still essentially a CALORIES IN - CALORIES OUT diet. You need to create a caloric deficit during the week that greatly offsets the weekend carb-up (if you do a carb-up). Some people like to claim that the weekend carb-up does not store fat, and that calories in - calories out does not apply. This is a fallacy! If you think that way, then you cannot apply any daily activity that burns glycogen during the week to the daily maintenance calories. Get it?

Furthermore, ketogenic diets have been shown to cause loss in lean body mass during the first three weeks more than other diets. After 3 weeks, there is less lean body mass lost than other types of diets. You need to diet for at least 8 weeks or so to reap any real benefit from a ketogenic diet.

Ketogenic diets cause your metabolism to DROP really quickly.

Ketogenic diets are not good for gaining Lean body mass. The carb-up in a CKD isn't extremely anabolic, either.

Ketogenic diets are useful if:
1. You will diet for OVER 6 weeks, and your %bf will be low for the last three weeks, necessitating the extreme conservation of LBM.
2. You are insulin resistant (don't do a CKD in this case, though).
3. You aren't using drugs that are fueled by carbs.

I have done a CKD before. It is not a bad diet, and it has it's place. I think an isocaloric diet is better, though.

 

[plornive]

Also,
the main reason people claim a ketogenic diet conserves lean body mass after 3 weeks is that gluconeogenesis (conversion of amino acids to glucose) is slowed. This does not make any sense. Glucagon is the hormone that signals gluconeogenesis to happen. Insulin prevents it. This means that there is possibly MORE gluconeogenesis on a ketogenic diet than others. There is a way to limit this, though --- by consuming enough protein to minimize muscle loss without causing too much glucose to be released into the blood. Probably around 60% of protein ingested on a ketogenic diet is converted to glucose (10% of fat and ALMOST 100% of carbs end up in the blood as glucose). This means that for every 100g of protein ingested, 60g of glucose end up in the blood. You need to consume enough protein to just about meet your brain's glucose requirements, and also your body's amino acid requirements. Carbs are very wasteful to consume in this diet. 0 carbs would be idea.

If you wanna know about ketogenic diets, I recommend Lyle McDonalds's book The Ketogenic Diet. He is totally to the point and doesn't bullshit you. He does not make it out to be the ideal diet, just one option out of many, which is realistic. Body Opus would be my next choice, as it is entertaining.

 

[virtualcyber]

Thanks for the insightful reply.

So it seems, to do ketogenic diet right, I need to survive only on burgers, bacon, eggs, etc. for eight weeks -- god no!!

I suppose I will eventually try it, but it sure sounds like torture!

 

[plornive]

WAIT! My last reply was incorrect. Actually I think that it is a valid claim that keto diets limit gluconeogenesis. Keto diets downregulate the enzymes that process blood glucose, and the body prefers fatty acids and ketones to glucose. This seems to be a good reason to believe gluconeogenesis is somewhat limited. The enzyme downregulation is also a reason that people have a kind of temporary insulin resistance when switching off of a keto diet. Isocaloric diets are good for this transition period.

Yes, I think CKDs freaking suck. I hate SPAM, egg yolks, flax seed oil, heavy whipping cream, fatty meat. YUCK! Isocaloric diets allow you the most freedom. All most bodybuilders really need change for an isocaloric diet is their carb to fat ratio. Just lower the carbs by eliminating most starches and sugars (try consuming most complex carbs early in the day and/or post-workout), and up the fat by adding only a little bit of natural PB, flax, salmon, etc.