Don't understand this insulin index thing!!

[alexsmom]

I was looking at this insulin index site because I heard it was more important then the Glucose index in determining what carbs are "better" for you to eat...however, both brown and white pasta and even grain bread had a significant lower score than brown rice...however, everyone poo poos these choices and says to stick with brown rice. Why?? I'll try to post the site here....

www.zonehome.com/zlib0025.htm

 

[coolcolj]

everyone is different, try it and see. For example whole wheat pasta is supposed to be a low GI carb and I got blood sugar crashes from it!!

 

[Vageta]

The insulin index is a relatively new concept so many haven't yet adopted it. Milk has always been considered low GI though it creates a fairly severe insulin spike nonetheless. Problem is when the GI was created the researchers "assumed" that blood glucose levels would closely mimic insulin levels. A lot of times this is true but sometimes it's not as we now know.

What I find interesting is the level of insulin response created by things like fish and meat. For years a lot of people have been shying away from carbs for the sole reason of keeping insulin at a minimum, yet these charts show that some fish and meat actually have a fairly significant insulin response rivaling some of the carbs on the list. Obviously they have a minimal effect compared to sugary foods, but nonetheless the insulin is present and probably higher than most have been lead to believe.

What I do find interesting is that studies show that some food mixing does not change the GI of a meal. It was widely thought that mixing protein and fat along with carbs would bring the entire GI of the meal down. It's been proven that protein and fat have little effect on the total GI of the meal, mostly due to the fact that they themselves have little effect on the GI in general. However mixing different GI carbs will have a very predictable effect. Mixing 50% of a carb that rates a 100 on the GI with 50% of a carb that rates as 50 would most likely net you a 75 GI total. Adding fat and protein to this equation won't change it much however.

 

[anthrax]

What I do find interesting is that studies show that some food mixing does not change the GI of a meal. It was widely thought that mixing protein and fat along with carbs would bring the entire GI of the meal down. It's been proven that protein and fat have little effect on the total GI of the meal, mostly due to the fact that they themselves have little effect on the GI in general. However mixing different GI carbs will have a very predictable effect. Mixing 50% of a carb that rates a 100 on the GI with 50% of a carb that rates as 50 would most likely net you a 75 GI total. Adding fat and protein to this equation won't change it much however.

are you sure ?
I thought fats and proteins would decrease the GI of a meal...

BTW I think II is mich more useful then GI

 

[Vageta]

Yes I read the bit about the protein and fat not having an effect on GI recently. I'll try to find the site again and post a link. It makes sense if you really think about it. The average American diet is high carb and high fat. If the fat intake really slowed down the GI of the meal that much then mainstream America would all be on a theoretical low GI diet and we probably wouldn't be as fat.

Nonetheless the study showed that the same 50g of carb ingested alone and with fat and protein caused similar blood glucose levels. However maybe mixing them does have an effect on insulin levels.

 

[FitnessFrk]

There are many things to remember about GI/GR, insulin index etc.

Whenever you eat insulin is secreted. High protein foods do not cause insulin to spike, as they do not affect blood sugar levels.

Carbs have a strange effect. One day (a moderate GI food) they can have a low effect on blood sugar while the same about taken on another day can cause insulin to spike, that's just the way the human body works.

The average American diet consists of high GI/GR carbs and very large servings. If you eat enough of a low or moderate GI/GR carb it can cause an insulin spike. So even with a high fat intake blood sugar can rise high enough to spike insulin. Then you have to factor in things like insulin sensitivity and insulin resistance from this constant intake of high GI/GR carbs. And of course the major factor is the sedentary lifestyle of the average American.

Athlete’s body function at a much higher level of efficiency so many of these things do not apply to us.

 

[plornive]

What confuses me is this:

Fat takes a very long time to digest. Carbs are digested very quickly. This means that carbs hit the bloodstream faster than fat.

So, how does mixing fat and carbs increase the insulin response? Or does it?

Maybe one needs to keep serum fat levels somewhat low while consuming carbs. This would require a long-term adherance to a moderate to low fat diet. Even though the liver would produce fatty acids, serum fat levels would be lower than if fat was ingested. This would also explain why eating healthy fats assists in fat-loss --- serum fatty-acids would consist of more unsaturated rather than saturated fatty-acids. Saturated fat decreases insulin sensitivity.

I am curious how II measurements are done. It seems long-term dietary habits (serum fat levels) and insulin sensitivity would play a large role in insulin response.