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Basic Nutrition question: why low insulin on high protein diets?

Anyone who knows, please educate me:

Charles Poliquin and Beverly International among others prescribe a extremely high protein intake (greater than 2g/lb.) along with low carbs. The idea behind low carbs is of course to reduce insulin secretion, which inhibits fat burning. But since excess protein converts to carbs with about 50% efficiency, how come this glucose doesn’t increase insulin appreciably? Is there some different pathway the converted carbs go through so that they do not increase insulin like dietary carbs? Brian

beverly international is a real good company, i used there supps and diet to get my bf down to 7.9 from 13 from july 1 2001-sept 10 2001

It’s the mixing of fat with proteins they use and the mixing of proteins that has a lot to do with it to curtail the insulin response. If you look over their recommended diet plans you’ll see higher fat animal type proteins like ground beef mixed with leaner proteins. They don’t recommend using straight whey either for the exact reason you bring up. Whey by itself increases insulin. A mix of different blends of protein such as whey and casein along with whipping cream in a shake leads to slower releasing and thus less insulin. As far as how much insulin increases through high protein intake vs carb intake I’d imagine it would be a lot lower for the protein no matter how much protein you consume. The body first has to convert that protein into glucose which takes time for it to do.

Many people forget that protein causes glucagon release.

Kelly, if whey produces a insulin spike when eaten on its own, why does little research show this???
L

Guys, I understand that they favor a balance between the “anabolic” and “anti-catabolic” proteins, so that insulin level isn’t raised that way. And of course, glucagon is working antagonistically, so that’s a factor. But that still doesn’t answer the question as to what happens to the excess protein. The body actually uses less than 1 gram per pound of bodyweight, so that leaves a lot of extra, roughly half of which will convert to glucose the other half to fat. It may be released slowly but it’s still there. How come the body doesn’t release insulin like mad and prevent fat burning?

Michael the research does show that whey increases insulin secretion. I can’t remember exactly where but try reading through the archives.

I just finished reading the ,main study on protein speed, Borrie et al in proceeding national accademy of sciences (i think). One of their origonal concepts about protein affecting protein balance was a difference in insulin levels. But comparing the 30g of protien from whey and casein showed no differences in insulin levels. Same in their later study in am J Physiol 2001.

Michael, excellent post. If you have any other info on this matter, please post that as well. Thanks.

What do the studies say about the speed at which this insulin is released into the bloodstream between these 2 groups? This is just as important. Even when speaking of carbohydrates typically X grams of carb will equal Y amounts of insulin but where we see all the major differences is the speed of release.

The studies dont provide specific information (text or graphs) on insulin, but they mention that no significant difference at hte time points over the 7 hour measuremetn periods

you need extra protein for nitrogen retention.