For those of us who depend on insulin to literally keep us alive, we often observe that it has another side to its nature, one that can harm us if we’re not careful. We all learn, early in our insulin dosing career, that the biggest drawback to insulin is when we take too much and it drives us hypo. That’s the more obvious negative consequence of using insulin but that is not the dark side that I’m writing about.
When I first started dosing insulin, I found that my meal doses and high-glucose corrections performed well. This encouraged me to lean into the power of insulin and deliberately slightly overdose to keep good control and also allow me the food treats that I was used to eating before my diagnosis.
While I had to keep my guard up watching for overcorrections and hypos, this system seemed to work for me. Over time, my total daily dose of insulin gradually ramped up. While my A1c remained in the mid-6% range I started gaining 1-2 pounds each year. A daily bicycle habit permitted me to eat all kinds of treats and then burn them off with a 1-2 hour aggressive cycling workout.
When my exercise habit waned, I started to notice that my high-BG corrections did not work as well, so I adjusted my correction factor (aka ISF) to permit more aggressive doses. I ended up 30 pounds overweight and my insulin correction doses often acted like I was injecting water.
They just didn’t work – until they did when I resorted to rage blousing that often meant a screaming white-knuckle descent into severe hypoglycemia (< 54 mg/dL or 3.0 mmol/L).
All those problems led me to learn some important lessons about using insulin. I learned that injecting more insulin than is needed, especially over enough time, causes insulin resistance. When I changed my way of eating and strictly limited carb consumption, my total daily insulin doses were cut to less than half of what I had been taking. I lost about 14% (25 pounds) of my body weight and my glucose corrections started acting rationally again.
Fast forward to today when I’m using an automated insulin dosing system comprised of a pump, CGM, and an algorithm stored on my phone. I recently updated the algorithm to one that instead of setting temporary basal rates to control glucose levels, it delivered small “microbuses” to maintain control.
Over a week’s time, however, I was alarmed to see that my total daily dose of insulin ramped up by 25% while my control degraded. My past experience informed me that this was not a good thing.
I know that this auto-bolus tactic works well for many so I’m sure that my settings were not optimal. But I wasn’t comfortable infusing so much insulin, so for the time being I changed back to my modulated temporary basal rate algorithm.
Yesterday, I decided to do a 36-hour fast to help bring my metabolism back into a decent balance. It seems that my sensitivity to insulin has returned to more usual levels. Fasting is a potent tactic with few downsides.
Insulin, like any powerful tool, has a bad side as well as a good one. If you abuse its power, it has shown me that its potency can evaporate. I don’t want to live without an effective, potent and rational-acting insulin in my kit.