What is Insulin Resistance and How Do I Reverse It?

Medically approved by Dr Tim Trodd

Family Medicine, Functional Medicine, General Practice

June 3, 2025

Understanding Insulin Resistance

Insulin resistance is a condition where the body's cells—particularly in muscle, fat, and liver tissues—do not respond properly to insulin, a hormone that regulates blood glucose levels. This impaired response means that glucose is not efficiently taken up from the blood into the cells, causing blood sugar levels to rise. To compensate, the pancreas produces more insulin, leading to elevated insulin levels (hyperinsulinaemia).

The Importance of Recognising Insulin Resistance

This condition matters because insulin resistance is a key factor in the development and progression of several serious metabolic diseases. It significantly raises the risk of type 2 diabetes, as the pancreas eventually cannot keep up with the demand for more insulin, leading to beta-cell dysfunction and the onset of diabetes. Insulin resistance is also strongly linked to cardiovascular diseases, non-alcoholic fatty liver disease, hypertension, dyslipidaemia, and even certain cancers. It contributes to metabolic disturbances in various organs and tissues, worsening overall health outcomes.

Signs and Symptoms

At a medical examination, we may observe high levels of fasting insulin, HbA1c (long-term sugar), LDL cholesterol, and triglycerides, as well as find fatty liver on ultrasound.

Factors Contributing to Insulin Resistance

Importantly, insulin resistance is associated with being overweight, physical inactivity, genetics, and other factors. We naturally tend to become more resistant to the effects of insulin as we age. However, it can be improved or even reversed through lifestyle changes such as increased physical activity, weight loss, and dietary interventions, which can reduce the risk of developing these related diseases.

Effective Lifestyle Changes

The most effective lifestyle changes to reverse insulin resistance focus on improving diet, increasing physical activity, and achieving weight loss:

Dietary Changes: Carbohydrate restriction is particularly effective, as it lowers blood glucose and insulin levels and promotes fat loss, which helps reverse insulin resistance. Calorie reduction to facilitate weight loss also improves insulin sensitivity by reducing abdominal fat. Diets low in saturated fat and high in dietary fibre are recommended to improve metabolic health.

Physical Activity: Regular exercise enhances insulin sensitivity by improving glucose uptake in muscles and reducing fat mass. Even low-intensity lifestyle modifications over eight weeks can significantly improve insulin resistance.

Weight Loss: Losing excess body weight, especially abdominal fat, is crucial. Weight loss achieved through diet and exercise reduces insulin resistance and lowers the risk of type 2 diabetes.

Sustained Lifestyle Therapy: Long-term adherence to these lifestyle changes can lead to remission of type 2 diabetes and restore normal glucose metabolism.

Weight Loss Medications: Medications such as Ozempic can play a role but must be accompanied by a lifestyle programme, or loss of muscle mass could make matters worse.

Conclusion

In summary, a combination of carbohydrate-restricted and calorie-controlled diets, increased physical activity, and sustained weight loss are the most effective lifestyle strategies to reverse insulin resistance and improve metabolic health.