IGF-1 Question

[Oceano]

Can someone please explain what 'negatively associated' means in the following excerpt:

'Because IGF-1 is a potentially important determinant of disease, especially cancer, epidemiologic identification of modifiable determinants of serum IGF-1 could be of clinical importance. We and others have recently shown that age, sex, and smoking are independent predictors of serum IGF-1 and IGFBP-3 concentrations.18,46,47 In this study, we demonstrate that consumption of red meat, oils, and fats as well as dietary fat intake is positively associated with serum IGF-1 and independent of other variables, whereas dietary carbohydrates and consumption of bread (a significant source of carbohydrates in the Greek diet) are negatively associated with serum IGF-1 levels. Saturated fat seems to be negatively related to IGFBP-3 levels only. The relationship between these nutritional variables on the one hand and serum IGF-1 or IGFBP-3 levels on the other hand has not previously been reported, to our knowledge.'

And what does 'inverse relationship' mean below:

'More specifically, hypoglycemia increases whereas hyperglycemia decreases growth hormone levels in humans,48 which is consistent with the inverse association between carbohydrate intake and serum IGF-1 levels observed in this study.'

http://jco.ascopubs.org/cgi/content/full/17/10/3291

 

[UncleBee]

Not a good thing, not possitive. Negative. I know, it sound wrong, but who knows, ......whatever.

 

[access]

Seems the study is indicating that carbohydrates, specifically a diet high in carbohydrates has a negative affect on serum IGF levels in the first paragraph. The second paragraph is stating that the relationship between carbohydrates, hyperglycemia and IGF serum levels is also intrinsically linked.

Looks interesting, will have to read the whole study.

 

[Oceano]

Seems the study is indicating that carbohydrates, specifically a diet high in carbohydrates has a negative affect on serum IGF levels in the first paragraph. The second paragraph is stating that the relationship between carbohydrates, hyperglycemia and IGF serum levels is also intrinsically linked.

Looks interesting, will have to read the whole study.

Cheers, thats what I thought.

I found that interesting since many would have you believe that more carbs = more IGF-1.

I have seen other sources which suggest that more carbs = less IGF-1

High IGF-1 comes from protein and fat. These are the real growth macronutrients it would appear.

Anyone any other thoughts on the study?

 

[access]

Cheers, thats what I thought.

I found that interesting since many would have you believe that more carbs = more IGF-1.

I have seen other sources which suggest that more carbs = less IGF-1

High IGF-1 comes from protein and fat. These are the real growth macronutrients it would appear.

Anyone any other thoughts on the study?

Ok I read the whole study and your summation is spot on.

 

[Tatyana]

Cheers, thats what I thought.

I found that interesting since many would have you believe that more carbs = more IGF-1.

I have seen other sources which suggest that more carbs = less IGF-1

High IGF-1 comes from protein and fat. These are the real growth macronutrients it would appear.

Anyone any other thoughts on the study?

The carb they stated in the paper is quite specific, BREAD, not all carbs, as all carbs are not equal.

 

[Oceano]

The carb they stated in the paper is quite specific, BREAD, not all carbs, as all carbs are not equal.

So what are you saying, bread lowers IGF-1?

There are other studies online showing that carbs reduce IGF-1.

What carbs do you think raise IGF-1?

 

[access]

The carb they stated in the paper is quite specific, BREAD, not all carbs, as all carbs are not equal.

I'm not certain that is totally correct. I think the reference was specifically to a Greek diet which itself is high in carbs because of the bread. All food groups were covered in the study per se but because the study subjects were from Athens the bread contributes to a high carb diet. This excert explains this in a little more detail:

The food groups formed were as follows: cereals; starchy roots; sugars and syrups; pulses, nuts, and seeds; vegetables; fruits; meats; fish; eggs; milk and milk products; oils and fats; and nonalcoholic beverages. Some cooked meals were allocated to two food groups (one half in each), as previously described.25 A number of items, important in the Greek diet because they are frequently consumed, such as olive oil, vegetable oil, cooking fat (usually of animal origin), butter, margarine, potatoes, and bread, were also considered individually. Macronutrient intakes for study subjects were estimated by multiplying the nutrient content of a selected typical portion of each food item by the frequency that this food item was consumed per month and adding these estimates for all items based on a nutrient database developed earlier in Greece.25 We first investigated macronutrients, ie, total protein, total fat, and total carbohydrate, and then estimated total energy intake, as previously described.23-25,29 Because macronutrients are positively correlated with total energy intake,24,30 energy adjustment was used in the analyses31 as indicated below. In addition, since body size may also contribute to the variation in specific nutrient intakes,31 we adjusted for its potential confounding effect in additional models.