Milk's effect on insulin

[hypo]

I drink skim milk, and the carbs in this milk, though sugar, are lactose, which is a low GI carb. I have heard, however, that milk creates a rather pronounced insulin spike. What is the spike equivalent to; is it big enough that milk intake should be limited?

I won't give up my skim milk either way, the only two things I drink are milk and water! I'm more curious why this spike occurs than anything.

[exnihilo]

My understanding is that it is caused by the high protein content in milk. There's so much evidence that dairy products contribute to leanness that I wouldn't worry about it.

[Sticks]

Seems like this would make skim milk a perfect addition to a postworkout meal/shake.

[Chunky]

I dont know how, but that is why we should consider the gi index but we should also check for insulin index.

[exnihilo]

I dont know how, but that is why we should consider the gi index but we should also check for insulin index.

The insulin index is fairly well correlated with the glycemic index, the biggest deviations are in things that have a significant fraction of quickly absorbed protein (the whey content in yogurt and milk being the likely culprit for their elevated insulin index score). In most cases I think you can just go by the GI.

[Dwight Schrute]

Most of time it is correlated but many items that have a high fat content that are very low on the GI have significant amounts of insulin release. Such items as Cottage cheese, Whole Milk, Eggs, Meats etc....have a much larger release of insulin even though their response is almost nil.


Milks effects on the response and release is relatively low when its skim milk. There was a study that showed some type of milk had higher insulin responses than what the GI was showing but the type of milk used was a Sedish brand with had virtually no response and the findings showed it has a low-mod response. This is due to the amino acid content but overall the response was still low-mod.

[dsl]

why is it that fat causes an insulin spike and not the carbs? is it because fat doesn't really have to be broken down to be stored in the body, so insulin is released to clear excess from the blood?

[Dwight Schrute]

It creates a larger release (amount) not an increased spike (response). As to why I don't know. Its fairly a new dicovery over the last couple years.

[Nitrox]

Fat triggers an insulin response because it can raise blood glucose. As Bobo said, it is not really known why yet - I asked my endocrinologist and got that answer. Some glucose can be made from the glycerol portion of fats but that's only about 5% (I think).

All food will eventually raise blood glucose it's just that carbs will do it faster. One has to take into account the rate of digestion/absorption as well as total caloric content. Adding a fat and protein to a carb meal may blunt the blood glucose spike but it will increase the duration and the area under the 'insulin curve.'

Being diabetic I shake my head at the trend towards 100g dextrose post workout shakes. An equivalent kcal milk/whey/flax oil shake is more than enough to keep me going pwo.

[dsl]

i thought the whole point of a post-workout shake was to shuttle nutrients away to the muscle. and, as you say, fat slows this down rendering the pwo shake useless. Also, i don't use dextrose, i use oatmeal as do many on this board. Furthermore, I don't know much about diabetes, but i imagine that you wouldn't have trouble incorporating them into your pwo shake-minus the fat.

[Nitrox]

i thought the whole point of a post-workout shake was to shuttle nutrients away to the muscle. and, as you say, fat slows this down rendering the pwo shake useless. Also, i don't use dextrose, i use oatmeal as do many on this board. Furthermore, I don't know much about diabetes, but i imagine that you wouldn't have trouble incorporating them into your pwo shake-minus the fat.

Sure that is the intended purpose of pwo nutrition but it seems that many people get this confused with triggering a large insulin response. Exercise temporarily improves insulin sensitivity - meaning that nutrient uptake under 'normal' insulin levels is increased. How high of insulin levels does one actually need to restore muscles?

Something that I have never seen numbers on is how much and how fast the body can shuttle nutrients to (depleted) muscle. Glucose (aka dextrose) is absorbed extremely fast; I question how much of the 80-100g dosages that many ppl use goes to fat storage vs lean tissues. Of course lean body mass, level of depletion, and previous meals would be factors.

Adding in fat would not necessarily make the said shake useless; is the overall rate of digestion/absorption that is important. Take the oatmeal for instance, on the GI scale it is about half of glucose. One could add in fat to a glucose shake and achieve an overall GI on par with oatmeal.

Anyhow my point was that I think it's possible that the big glucose shakes are possibly overkill.

FWIW when I'm dieting I do use about 15g of oatmeal in a pwo shake (150lbs @ 8-10%) but when I'm trying to build my priority is minimizing insulin levels while maintaining positive energy balance.

[Dwight Schrute]

i thought the whole point of a post-workout shake was to shuttle nutrients away to the muscle. and, as you say, fat slows this down rendering the pwo shake useless. Also, i don't use dextrose, i use oatmeal as do many on this board. Furthermore, I don't know much about diabetes, but i imagine that you wouldn't have trouble incorporating them into your pwo shake-minus the fat.

Insulin's main action at increasing nutrient uptake is by increasing GLUT4 permeability by vasodialation. This happens regardless because of exercise so the need for insulins actions on nutrient uptake is minimal. Insulin primary role is more an anti-catabolic one and the amount need to exer this effect is rather small.

[dsl]

Insulin's main action at increasing nutrient uptake is by increasing GLUT4 permeability by vasodialation. This happens regardless because of exercise so the need for insulins actions on nutrient uptake is minimal. Insulin primary role is more an anti-catabolic one and the amount need to exer this effect is rather small.

then is there really a benefit to using carbs p/w rather than fat, or vice versa.

[Dwight Schrute]

Of course. You want an insulin release. You just don't need a very large on to get the effects.

Fat has no effect on glycogen synthesis. You are grouping some fats that increase the insulin load (amount) with all fats and they don't work like that. Leave fats out of your post workout shake. The insulin load and response it completely different things and you are grouping then together. It doesn't work that way.

[xxghostxx]

Insulin's main action at increasing nutrient uptake is by increasing GLUT4 permeability by vasodialation.

Hey Bobo, could you explain why it is that GLUT 4 translocation occurs in an insulin independent manner during exercise? Not that it matters, as it's going to do it regardless... I'm just curious.

[Dwight Schrute]

To increase nutrient uptake to counter the effects of resistance training.

[xxghostxx]

To increase nutrient uptake to counter the effects of resistance training.

Eh,reasonable enough