Why would I need less insulin

I have a very set routine for taking care of diabetes. I eat the same things for breakfast everyday and then get on my exercise bike and ride 3.5 miles. At lunch I eat the same thing almost everyday and then ride another 3.5 to 4 miles. This works very well for me and keeps my glucose levels in a tight range and my A1c very low.

For the past 3 days I suddenly need less insulin. The first day I had to skip exercising all day because I had too much insulin on board. The next day I took less Novolog and was able to ride in the morning, but not in the afternoon even though taking less Novolog. This morning I will go low if I ride. I hate missing my exercise. I am down to 20 units of insulin total without much exercise.

I don’t get it. My dinners haven’t changed. Tomorrow I will lower my Tresiba. I am not complaining, I like being able to reduce my insulin, I just don’t get it.

Could it be from my Moderna vaccination I received 19 days ago? I didn’t notice any changes when I was first vaccinated.

So strange, I ate oatmeal, banana, walnuts, a date, and blueberries for breakfast and returned to a 90 glucose level an hr later. I didn’t rise over 100. I took 3 units of Novolog. I did not exercise. I am holding steady at 91. This is weird.

This is kind of what it’s like for me too.
Just when I think I have it down, it changes. I think it’s a bit of flowing and ebbing insulin resistance.
I can go from 45 units a day to 60 and eating essentially the same thing.
Of course I have a pump so there are absorption issues as well.
When I lose a little weight or gain a little it all seems to change

However my range stays the same. I average around 50 units since I started tracking it in my early 20s.

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Marilyn, I think this change in insulin sensitivity is common to many of us. I went through a several day period last month when my total daily dose of insulin (TDD) went down from the high 20 unit range to 20 units, about a 1/3 decrease. But then it climbed back up toward a 30-unit TDD a few days later.

All I can conclude is that these slower rolling changes are just part of the normal ebb and flow of human metabolism. All we can do is respond by reducing insulin when that happens and then adding it back if/when needed. I also miss some exercise days when this happens.


It is weird though, because I have been following this pattern of eating and exercise for a long time and my weight doesn’t really change.

I find my insulin needs (and A1c) go up in the fall and winter months and down in the spring and summer months. So I’m expecting my insulin needs to fall any week now. Could that be it?

Or maybe you’re less stressed now that you’ve had the vaccine? Maybe you’ve had a low level of constant stress for the past year that’s now gone?

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Thanks for the ideas Jen. Definitely a bit less worried about Covid, but still waiting to hear about my husband’s heart, so still stressed. Also worried about my second vaccination.

Interesting that your insulin needs drop in the Spring. That definitely could be a possibility!

Marilyn -
I have a doctor who has a very dry sense of humor. Several years ago, when I was having a similarly weird situation (days of ups and downs with no apparent reason…eating the same food, same exercise, etc.) my doctor said, “Well, diabetes is a very weird disease so, I think weirdness with D is actually pretty normal.” About a week after that, with no change in regimen or insulin dosages, my numbers went back to normal.

So…is this a weird disease, or what?!

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Very Weird so that we don’t get bored!

You know something that just occurred to me.
You are likely passed hormonal changes so we can eliminate that.
I read that there are some vaccines that alter your immune system enough for you to start producing some insulin again.

I know it seems far fetched since you are more than 60 years in.

I was just yesterday reading about a new study that uses a known vaccine (for something else) Triple in strength in hopes to see some increase in c-peptide.

However it was only for those diagnosed less than 5 years.

Anyway it’s possible you got some of that effect. Hard to say without a blood test, but it’s in the realm of reasonable.

Well wouldn’t that be nice, although that would be more like a miracle. :grinning:

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