What would happen if I let my friends try taking an injection of insulin? Since they don't have diabetes, would it not make any difference in their bodies?
That's a really important question because I have a few friends who often make jokes about giving themselves an injection of my insulin. I've let some of my friends try testing their blood sugars using a clean lancet and a new test strip, but I do not let my friends try taking injections.
When a non-diabetic takes a shot of insulin, they will definitely have a low blood sugar shortly afterwards if they don't eat a lot of carbs to compensate. Bodybuilders take insulin when they're trying to help their muscles grow because the more carbohydrates they can get their bodies to absorb, the more they'll grow. However, even many of these bodybuilders have had really bad low blood sugar incidents because they aren't aware of exactly how many carbs they need to cover how many units of insulin. Additionaly, some experts consider this practice to be drug abuse. Insulin use is prohibited, in non-diabetic athletes, by the International Olympic Committee.
The same goes for any of your friends: we don't know what they're bodies need for a carbohydrate-to-insulin ratio and there's really no need to figure this out, because it's really dangerous!!
As for letting your friends test their blood sugars, I don't think there's any problem with doing this occasionally as long as you use a clean lancet, make sure they clean their hands well and make sure that the used lancet and the test strip with the blood on it is disposed of properly! Meanwhile, though, test strips are expensive so this shouldn't become a regular thing.