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The Rise And Fall of Insulin


Obviously the amount and length of time that insulin is elevated depends on many factors. However, say one consumed a large amount of carbohydrates (say 100 grams). Can anyone give an approximate figure as to how long insulin would remain elevated before someone could get back into a state where fat burning is feasible?

I've heard that a large amount of carbs will spike insulin for most of the day, and I've also heard the standard figure of several hours.


NO :slightly_smiling:

sorry to many factors. what kind of carb, what else was with it etc etc.

Like 100grams in the form of Surge would be gone like NOW leaving your blood sugar crashing and NEEED FOOD!! Same with many soda and processed foods. Now 100 grms of oats and fruit would give much less a spike and more a gradual rise and fall



Agree with phil, there's just too many things to take into account to say for sure what would happen.

I would expect that you should focus on fat burning during your "off" days from the gym. Just do some jogging or something to get you're heart rate up on days when you don't need to spike insulin and you can achieve reliable fat burning. The effects of insulin on those days shouldn't be a problem, so I would do that just to play it safe.


There actually are some good rules of thumb. 2 hours is generally the limit at which your insulin will be spike from a basic meal. As others have said, this time will vary depending on the food you ate. Some carbs, if they are really the slowest digesting types, will likely not spike your insulin in the first place, just elevate it. It could take more than 2 hours to drop, but it shouldn't take much more than that.

The real question here is why you think you only "burn fat" when your insulin is not spiked. It's really so much more complicated than that and you need to worry about the bigger picture.


Glucose concentrations following C (carb drink - vitargo) or G (glucose drink with a mix of dextrose and malto). Grams of carbs is unknown, thoug it's probably safe to assume the study was done w/ fairly typical PWO quantities.

Eur J Appl Physiol. 2000 Mar;81(4):346-51. Links
Muscle glycogen resynthesis rate in humans after supplementation of drinks containing carbohydrates with low and high molecular masses.


My bad - I meant to say "more feasible" instead of "feasible."


Not eating carbs by themselves is one thing that really makes a difference. Once in a while if I eat some plain potato or something and get sidetracked my blood sugar will spike pretty hard. If I put some butter on it and eat some other carbs and some protein it'll rise 20 or 30 mg/dl.