Insulin not lowering levels?! Can Type 1 become insulin resistant?

Hello, I'm looking for some advice. My glucose levels are almost impossible to bring down and my insulin is at almost double!! What is happening?
Sorry about the massive backstory, any help would be so greatly appreciated.

I've had Type 1 for 10 years and have had a pump for the last 6 years.
I have been using the Animas Vibe (2020 before that) and have been using Dexcom CGM for the past year.

Last year I lost quite a bit of weight (about 8 kilos) and since I was going to the gym almost every day and eating very few carbs, my daily insulin was reduced to about 20 units,. Previously it was about 50 units but I was eating a lot more carbs and I assume my insulin sensitivity was lower because I didn't exercise every day. I reduced my basal, Insulin to carb and ISF all quite dramatically and my levels were perfect for a few months.

My endo has now told me I need to stop losing weight (possibly gain a few kilos) as my estrogen levels have become a little low...

I've reintroduced more carbs into my diet and I'm not going to the gym as frequently, in order to not be in a calorie deficit.

Recently, my BGL's have been consistently high, almost all the time. I've increased basal a little and have been bolusing more with the extra carbs, but it just keeps going up and I can't seem to bring it down.

While I was losing weight I became a little fearful of insulin because of weight gain, and I can't seem to shake that feeling.

Does anyone know what's going on? Have my ratios all reverted to normal? Have I become resistant to insulin? Will the extra insulin cause me to gain weight?

I'm getting very worried about my Hba1C..

Thanks to anyone who has some advice!!

Hi -

I'd suggest gradually increasing your basal and adjusting your carb ratio until you begin to get your numbers back into range. I've found that when I gradually increase my basal, I get no results until I suddenly hit the sweet spot and everything begins falling into place.

Insulin needs change all the time as I'm sure you know. We need what we need and there isn't much point worrying whether it's too much. One way to gain or maintain weight without having to worry as much about your blood sugar is to increase the number of calories that you get from healthy fats including olive oil and nuts.

Good luck,


The simple answer to your question is, yes, T1Ds can become insulin resistant. It's just strange that your resistance follows a significant reduction of insulin total daily dose about a year ago. But there could be other reasons for an increase in insulin usage, such as a poor site absorption or infection.

Are you confident about the quality of your current insulin source? Is it possible you got a bad vial? Has your insulin supply been subject to very hot or freezing temperatures? Have you considered switching to a new insulin bottle and see if your control is any better?

Do you have any active infections, whether viral or bacterial, for example, a urinary tract infection?

You might experiment with a change of infusion sets, perhaps going from a 90 degree cannula to a 30 degree cannula, or vice-versa, maybe at a different depth. You might also try some steel sets. They're not as bad as they sound, the needles are small gauge and not very deep, but you can only wear them for two days, instead of three. But they're very resistant to occlusions and bent cannulas will not happen.

If you've been using the same general area to infuse, such as your abdomen, you might consider finding some alternate sites. Fresh new tissue makes for better and consistent absorption.

You could try a 24-hour fast. That always shakes things up metabolically for me. I go from dinner one day to dinner the next. It's not that hard and I always feel more alert.

You could start logging everything or at least uploading your devices to a central service, like Diasend, for analysis.

Sorry if I've given you way more to consider than you thought. You just need to try a few different things and see what might work.

Good luck.

Thank you for your advice!
This helps a lot, I will open a new vial and see if anything changes.
I do change my site about every second day as I find the absorption slows down the longer I leave it in.
I've been using diasend since I got my pump it's a godsend!
Different infusion sets are something I haven't considered but sounds like a good idea, since I often struggle finding a site the right amount of fat to insert it. I find the absorption speed also varies depending on whether the cannula is on my hips or stomach but I always stay close to the abdomen.
I will look into the steel sets I've never tried them before.
Thanks again!

Thank you for your reply!
This is really great reassurance, I guess I just need some more insulin, and a few more calories.