Insulin Resistance

Insulin resistance is a condition in which muscle, fat, and liver cells respond poorly to insulin, forcing the pancreas to pump out more of it to keep blood sugar in a normal range. Left unaddressed, it can progress to prediabetes and type 2 diabetes, and it's a core feature of metabolic syndrome. Carbohydrate restriction is one of the strategies studied for improving it.

Medical disclaimer. This article is for general educational purposes only and is not medical advice. It is not a substitute for professional diagnosis or treatment. Always consult a qualified healthcare provider before starting the ketogenic diet or making changes to your diet, exercise, or medication — especially if you are pregnant or breastfeeding, take medication, or have a medical condition such as diabetes, or kidney, liver, or heart disease. See our editorial & medical-review policy.

What causes insulin resistance?

Insulin resistance develops when cells stop responding normally to insulin's signal to absorb glucose, usually building up gradually from a mix of excess body fat (especially around the abdomen and organs), physical inactivity, and genetics.¹ As cells resist the signal, the pancreas compensates by secreting more insulin, which can keep blood sugar looking normal for years even as the underlying resistance worsens.

How is it linked to type 2 diabetes and metabolic syndrome?

Insulin resistance is the metabolic problem that typically precedes type 2 diabetes: as cells resist insulin, blood sugar creeps upward until the pancreas can no longer keep pace.² It's also one of the defining features of metabolic syndrome, alongside high blood pressure, elevated triglycerides, and abdominal obesity. Doctors sometimes screen for it using a fasting insulin level or the HOMA-IR calculation, both of which are things to review with your own healthcare provider rather than self-diagnose from.

Can a low-carb or keto diet improve insulin resistance?

Reducing dietary carbohydrate lowers the amount of insulin the body needs to release after meals, and several clinical studies report improved insulin sensitivity markers on lower-carbohydrate diets.¹ This is one mechanism behind the benefits of the keto diet for people with insulin resistance or type 2 diabetes, though individual response varies and effects should be tracked with a clinician, especially for anyone on glucose-lowering medication. See is keto right for you for who should talk to a doctor before starting, and the science of ketosis for how lower insulin enables ketone production.

Frequently Asked Questions

What are the warning signs of insulin resistance?

Insulin resistance often has no obvious symptoms early on; it's typically identified through blood tests like fasting insulin or glucose, sometimes alongside signs such as skin darkening (acanthosis nigricans) or difficulty losing weight.

Is insulin resistance reversible?

For many people, yes — losing excess weight, increasing activity, and reducing carbohydrate or overall calorie intake can meaningfully improve insulin sensitivity, though this should be pursued with medical guidance, especially if you take diabetes medication.

Does keto cure insulin resistance?

No diet cures insulin resistance outright. Keto and other low-carb approaches may improve insulin sensitivity markers for many people, but results vary and should be monitored with a healthcare provider.

How is insulin resistance diagnosed?

There's no single home test; clinicians typically use fasting insulin, fasting glucose, an oral glucose tolerance test, or the HOMA-IR calculation, interpreted alongside your health history.

See also

• Insulin
• Glycemic index
• Gluconeogenesis
• Full glossary index

Works cited

1. Insulin Resistance & Prediabetes — National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) — August 19, 2026 https://www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes/prediabetes-insulin-resistance
2. Insulin Resistance — StatPearls, NCBI Bookshelf — August 19, 2026 https://www.ncbi.nlm.nih.gov/books/NBK507839/

Article history

1. August 19, 2026First published