The fourth variable is the hardest one — because it has nothing to do with food or insulin and everything to do with the rest of your life.
Today's idea
Stress raises blood sugar. So does illness. So does poor sleep. So do hormones — across the menstrual cycle, across pregnancy, across perimenopause, across pubertal growth spurts. So does the weather, weirdly. So does any major change in your day-to-day routine.
People with Type 1 sometimes blame themselves when their numbers shift without an apparent cause. They retrace their bolus math, second-guess their meals, question their insulin. The cause is often none of those things. The cause is that they're a body, in a life, with many inputs.
The Pro Tip series captures the principle:
Hormones affect insulin sensitivity. So does stress. So does illness. So does poor sleep. None of these have anything to do with what you ate or what you bolused — and all of them show up in your numbers. Naming them stops you from blaming yourself for the wrong thing.
From Pro Tip 1447
Naming this variable doesn't fix it. But it gives you something to discuss with your care team that's more useful than "my numbers are weird."
The variables outside the food and the insulin are real. I don't have to explain them to count them.
Today, notice anything in your day that isn't food and isn't insulin but might be affecting your blood sugar. Stress. Sleep quality. A hard conversation. A long flight. A workout that was different than usual. Just notice the existence of the variable.
Small Sip #1470 — That's Just Diabetes
What variable did I notice today that I might not have thought about a week ago?