I had an insulin pump for over four years. I learned a lot about Insulin from using the pump.
One of the things that I learned about Insulin injection is that insulin injection points need to be moved after a while. The reason is that the area around the injection becomes Insulin Resistant and insulin isn’t as effective in that area. Eventually, a whole part of the body becomes unusable and may remain that way for years. I could no longer pump into the area to the sides of my navel. It gets harder and harder to find a place to pump Insulin. There are limited areas to pump. Some are pretty hard to reach, uncomfortable or just plain impractical.
The other thing I learned is that there’s localized fat deposited in the same area as the Insulin injection point was placed. This fact has been noted in the literature for almost 70 years (Renold AE, Marble A, Fawcett DW. Action of insulin on deposition of glycogen and storage of fat in adipose tissue. Endocrinology. 1950;46(1):55–66.).
SOON after the discovery of insulin, clinical observers reported the occurrence … hypertrophies (Eeg-Olofsson, 1930; Rowe and Garrison, 1932) of subcutaneous adipose tissue at the site of repeated insulin injections. A number of case reports and statistical studies have since been published. … lipodystrophy without evidence of inflammation has not been reported following injection of substances other than insulin. The production of insulin lipodystrophies in animals has been attempted by Reed, Anderson, and Mendel (1930), Marble and Smith (1942), Goldner (1943) and Oesterreicher (1947) with conflicting results.
In the search for an explanation of the effect of insulin on the adipose tissue of diabetics, various factors not concerned with the actual metabolic action of insulin have been suggested but supporting experimental evidence has been lacking (Marble and Smith, 1942).
This is interesting to me because of excess skin. My fat was enlarged by Hyperinsulinemia both from diet and exogenous Insulin.