What is insulin resistance and can I reverse it?

Insulin resistance is not a disease, but an early signal that your metabolism is falling out of balance. Your muscles, liver and fat tissue become less responsive to insulin, the hormone that regulates your blood sugar. The pancreas compensates by producing ever-increasing amounts of insulin, but eventually becomes exhausted. The result: rising blood sugar and possibly type 2 diabetes^1,2,3,4.

The most common cause is excess body weight. When fat cells become too large, they leak fatty acids and inflammatory substances into the bloodstream. Those fatty acids accumulate in the liver, muscles and pancreas, where they disrupt how insulin works. The liver is the organ most sensitive to this process. Prolonged excess weight also causes a low-grade inflammation throughout the body that further drives insulin resistance^5,6,7.

There is also a vicious cycle. High insulin levels make the resistance worse: the blood-sugar-lowering effect of insulin diminishes, while its fat-storage-promoting effect remains fully intact⁴. In addition, insulin resistance damages your blood vessels. Insulin normally causes blood vessels to dilate, but this works less effectively, leading to higher blood pressure and a greater risk of cardiovascular disease⁸.

For many people, insulin resistance is reversible. Exercising more and eating more healthily are by far the best-supported approaches^2,3,1. Medications such as metformin and GLP-1 agonists, a newer class of drugs that also help with weight loss, are effective additions. However, no drug has yet been officially approved with 'reversing insulin resistance' as a treatment indication^2,3.

That said, it is not equally achievable for everyone. Genetic predisposition, ageing, certain medical conditions, some medications and your gut bacteria all play a role. Lifestyle improvements therefore work much more powerfully in some people than in others. Realistic for many, then, but guaranteed for no one^5,2.