Insulin Resistance: The Hidden Link Behind Five Major Chronic Diseases

Insulin resistance does not only lead to type 2 diabetes – it sits underneath many of the chronic conditions that are now so common in midlife and beyond.

The hopeful part is that by improving insulin sensitivity, you are working on several diseases at once—not just your blood sugar.

Here are five major conditions that are strongly connected to long-term insulin resistance:

1. Type 2 Diabetes and Prediabetes

Insulin resistance is the engine behind prediabetes and type 2 diabetes.

Over time, the pancreas cannot keep producing enough insulin to overcome resistance. Blood sugar levels rise, and you move through “borderline” sugar levels to a diabetes diagnosis.

2. Heart Disease and Stroke

Insulin resistance is a key driver of metabolic syndrome – the cluster of high blood pressure, high triglycerides, low HDL, increased waist size, and impaired glucose regulation.

This combination greatly increases the risk of coronary artery disease, heart attack, and stroke, even before diabetes is diagnosed.

3. Fatty Liver (MASLD/NAFLD)

When insulin levels are high, the liver turns excess glucose and fructose into fat and stores it in the liver itself. This leads to metabolic dysfunction–associated steatotic liver disease (MASLD), previously called NAFLD (Non-Alcoholic Fatty Liver Disease).

Fatty liver is now one of the most common liver diseases and is tightly linked to insulin resistance, abdominal obesity, and type 2 diabetes.

4. Chronic Kidney Disease (CKD)

Insulin resistance and high insulin levels are associated with a higher risk of developing chronic kidney disease—even in people who do not yet have diabetes.

Insulin is particularly toxic to podocytes – the delicate cells that wrap around the tiny blood vessels in the kidney filter. A hyperinsulinaemic environment can injure these cells, damage the filtration barrier, and promote scarring over time.

5. Brain Conditions, Including Dementia

Insulin resistance in the brain is linked with worsened cognitive function, mood changes, and a higher risk of dementia, including Alzheimer’s disease.

Higher fasting insulin and HOMA-IR scores are associated with more brain atrophy and a greater chance of later cognitive decline, even in people who do not have diabetes.

Why This Matters for You

These conditions are often treated as if they’re separate — one clinic for your blood pressure, another for your liver, kidneys, or memory. In truth, they share a common metabolic root: long-term insulin resistance driven by modern food, chronic stress, poor sleep, and low movement.

The good news is that you can help your body become more insulin sensitive and support your metabolic health through what we call the 6S:

• Sustenance – Nourish your body with low carb, real food that keeps blood sugar stable.

• Sleep – Prioritise deep, restorative rest to balance hormones and energy.

• Strength – Build muscle through regular movement and resistance training.

• Stress – Manage life’s pressures with mindfulness, relaxation, and self-compassion.

• Sunlight – Soak up natural light daily to support mood and vitamin D.

• Social Connection – Stay engaged with loved ones; connection strengthens emotional and physical wellbeing.

Every small improvement in one of these areas helps reduce insulin resistance and supports your heart, liver, kidneys, and brain — all at once.

Dr Mary Barson and Dr Lucy are the founders of Real Life Medicine. They help women who have been on every diet under the sun, optimise their health and achieve long lasting weight loss without feeling miserable or deprived.

They do this with their 3 step framework:

• Strategies to improve your metabolism
• Brain-based skills to overcome self-sabotage
• Tools to make it easy to implement

With this comes increased energy, vitality and confidence.

You can avoid chronic disease and stop living life on the sidelines!