How high can your blood glucose level be until insulin is released and fat storage begins? I know it has something to do with degree of carb depletion but I don’t know much more.
I believe a normal, healthy individual will begin to release insulin once they rise above something like 100 mg/dL. Remember though, a healthy functional human body is extremely sensitive to changes in its blood glucose level. So for example your fasting (or target) glucose is 65-85 mg/dL. It won’t take much to get yourself to start secreting insulin to keep it in this range. The same can be said for the reverse situation with hypoglycemia and glucagon production.
Generally directly after a meal, assuming that it is digested and absorbed quickly, you will jump into the 150-200 mg/dL range. This is immediately followed by the trigger to process proinsulin and send your BG on the downfall.
Also don’t think of it as fat storage unless you are ingesting a lot of fatty material.
Insulin first and foremost causes you to store glucose in the form of glycogen. Notice there is no use of the word fat in that sentence. So unless you are eating lots of fats, insulin will not cause storage of these materials in fat deposits. But if you are eating Burger King all day, that is another story…
That’s an interesting question, but it just doesn’t work that simply. In fact, the pancreas is primed to secrete insulin immediately when food hits the small intestine. The small intestine starts releasing an insulin secretagogue hormone called GLP-1 when it senses food entering. Plus there is no set level where fat storage begins. It depends on your insulin sensitivity, activity level, liver function etc. Any time your blood glucose level rises above your fasting glucose level, the body will look for ways to bring it back down to baseline for you.
I think the trick is to keep the insulin sensitivity of your muscles fairly high, and keep your glycogen stores low by being active. That way glucose is shunted to your muscles preferentially instead of to fat.