Comment by syrrim
5 years ago
Different formulations of insulin offer different benefits to diabetics. Ones that are more slow acting more closely resemble the body's natural regulation of insulin, and therefore do less harm to the body. Or so I hear.
Most type 1 diabetics take 2 types of insulin (except for people on pumps). One is your bolus insulin, which is faster acting, usually used before meals or to bring down high blood sugar more quickly. The other is your basal insulin, which is slower acting, typically taken once or twice a day, which provides insulin for your body's background metabolic processes. People on pumps typically just use the bolus type insulin, since the pump can continuously supply small doses every few minutes, which allows for finer tuning more quickly.
Until about 25 years ago, the normal bolus insulin was Regular insulin, which is just like what your body makes. However, injecting it into fat makes it work more slowly, so you'd take it a half hour before eating, and it would peak a couple hours later. Currently bolus insulins are a genetically tweaked version that allows the body to absorb it more quickly, within a few minutes, with a peak in an hour or so. In the human body, there's an even faster phase 1 insulin response, but to get it as a type 1, you'd need to inject insulin into a vein. It can be done, but it is considered extremely dangerous.
Basal insulins are generally regular insulin mixed with something to delay action or modified to do the same. Older ones like NPH needed to be taken roughly every 12 hours, but had a relatively high peak, which sometimes meant you needed to time a snack to deal with that. Newer ones offer a much flatter action curve, and can often be taken just once a day.