A new clinical trial from the Garvan Institute of Medical Research has found that a cheap and widely used diabetes drug, metformin, can help people with type 1 diabetes reduce the amount of insulin they need.
This discovery could change how doctors treat type 1 diabetes and reduce the daily burden for people managing this lifelong condition.
Type 1 diabetes is an autoimmune disease where the body’s immune system attacks insulin-producing cells in the pancreas. As a result, people with this condition must inject insulin for life to control their blood sugar levels.
Managing insulin is difficult—it’s estimated that people with type 1 diabetes make about 180 extra decisions every day to stay healthy.
Some people with type 1 diabetes also develop insulin resistance, meaning their bodies stop responding to insulin. This condition makes it even harder to control blood sugar and increases the risk of heart disease, which is one of the leading causes of complications and early death in people with type 1 diabetes.
To find a better solution, Garvan researchers led by Dr. Jennifer Snaith and Professor Jerry Greenfield ran a clinical trial involving 40 adults with long-term type 1 diabetes.
Half of the participants received metformin and the other half received a placebo for six months. The goal was to see whether metformin could reduce insulin resistance, as it does in type 2 diabetes.
Surprisingly, metformin did not improve insulin resistance or blood sugar levels in these patients. However, it did reduce the amount of insulin they needed by about 12%. While this may not sound like much, it’s a meaningful improvement for people living with the stress of constant insulin use.
The research team is now exploring how metformin works to reduce insulin needs. One theory is that it affects the gut microbiome—the trillions of bacteria in the digestive system. Some studies suggest that metformin changes these gut bacteria in ways that may affect how the body uses insulin. This is an area the team plans to study next.
Metformin has been used for nearly 100 years, mostly for treating type 2 diabetes. Despite its long history, scientists still don’t fully understand how it works. This study suggests it could have an unexpected and useful role in helping manage type 1 diabetes as well, especially for people who struggle with large doses of insulin.
The findings offer new hope for better treatment options and fewer daily struggles for those living with type 1 diabetes.
If you care about diabetes, please read studies about diabetes and vitamin B12, and the right diet for people with type 2 diabetes.
For more health information, please see recent studies about how to eat smart with diabetes, and turmeric and vitamin D: a duo for blood pressure control in diabetic patients.
The study is published in Nature Communications.
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