FINALLY! A Small Study Looking at Tirzepatide in Type 1 Diabetes!

Original posted at obesity.news/ on Nov 20, 2025

Every week people in our community who live with type 1 diabetes reach out and tell me the same thing. They feel left behind. They feel like all the progress with GLP-1 medications somehow skipped over them. They have been told for years that weight management is not possible for them, or that tools like Zepbound and Mounjaro are too risky, or that there is simply not enough evidence. They carry the same food noise. The same weight. The same exhaustion. But none of the support.

This study recently published by the American Diabetes Association gives those people something real.

It is small. 24 adults with type 1 diabetes and a BMI above 30. Half on tirzepatide and half on placebo. 12 weeks. That is all. But even though the trial is small, the glimmer of that some hard data like this offers cannot be understated. When tirzepatide was added to the picture for this small number, things began to move in a big way.

The tirzepatide group lost an average of a little nearly 23 pounds in 12 weeks. 8.8% of their body weight. Every single person in the tirzepatide arm lost at least 5%. Almost half passed the 10% mark. The placebo group barely moved. This is the same pattern we have seen across obesity trials for years. The same pattern people in our community talk about when they finally feel their biology quiet down instead of fighting them every minute of the day.

For type 1 diabetes this matters even more because of what insulin does to the body. Many people in our community feel trapped in the vicious cycle of more insulin leading to more weight which then leads to more insulin. Tirzepatide broke that cycle in this study. Total daily insulin needs dropped by 24 units. The placebo group saw no real change. A1C also improved. Not by a huge amount but in a way that shows that lower insulin needs did not create chaos or instability.

And here is the part that will matter the most to anyone who has ever been told that GLP-1 medications are too dangerous for type 1 diabetes. There were no significant safety issues. None.

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For the first time we have controlled data showing that tirzepatide can help people with type 1 diabetes lose weight without the disasters that so many doctors have warned about.

To be clear, this is far from the final word. Again it just is a study of 24 people. It lasts 12 weeks. It will not convince every doctor. Sadly, it will not suddenly unlock wide access. We need larger trials. We need longer follow up. We need data on time in range and hypoglycemia and what happens during dose escalation. We need more.

But this is just the type of study that can lead to just that. More.

We have something people can print out and hand to their endocrinologist when they say they are tired of being ignored. We have something to point to when people are told that obesity in type 1 diabetes is just a discipline issue or a carbs issue or an insulin issue. We have something that shows this is a real medical condition with a real medical treatment that looks like it actually works.

Most importantly, it gives people in our community who live with type 1 diabetes the one thing they have not had in this space. Hope.

Send this to someone who needs hope. Send it to your doctor if you have ever been told that medication assisted weight loss simply is not possible for you. This is a win. A small win. A short trial. But a very real one.

Stay tuned to On The Pen for more updates on this study and on everything happening in the world of GLP-1 medications. And if you want a deeper dive into what larger trials could mean for access and coverage, I will be breaking that down soon.

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