Rod Munch wrote:
What will put you at risk for type 2 diabetes is not exercising, (which will diminish the activity/sensitivity of the insulin receptor and GLUT-4 glucose transporter in muscle cells), being fat (which will cause a chronic inflammatory state, producing cytokines that will damage the insulin receptor), and genetics (inheriting genes that will give you insensitive insulin receptors). All of these will make your insulin much less effective, causing high blood glucose levels.
You, being thin and active, are not going to develop type 2 diabetes by eating a banana on an empty stomach.
Very good. I was going to mention some of that. If you exercise, you produce less insulin than someone who doesn't; however, you're actually more sensitive to insulin (and thus regulate blood sugar levels more tightly) than a sedentary individual due to an upregulation of insulin receptors. This means that people who exercise are much less likely to get diabetes type II than those who don't.
As far as doctors not knowing about nutrition, any doctor who knows the same or less than Joe Public is a terrible doctor. Anyone who takes a few physiology classes should understand nutrition better than most nutritionists.
Tennis players eat bananas for the potassium to avoid hypokalemia.
Anyway, like I said in my first post, I wouldn't worry too much about it. Like Mr. Munch said, you're not going to get diabetes from eating bananas. If you're exercising, eating fruit and vegetables regularly and avoiding junk food like candy and soda, you're likely doing very well.