Insulin resistance is the metabolic engine behind most PCOS symptoms. Understanding it changes how you think about the condition.

What normally happens: You eat food → blood sugar rises → the pancreas releases insulin → insulin tells cells to absorb glucose → blood sugar returns to normal.

With insulin resistance: Cells don't respond efficiently to insulin → the pancreas produces more insulin to compensate → chronically elevated insulin has downstream effects throughout the body.

How elevated insulin drives PCOS:

• Stimulates the ovaries to produce excess androgens • Disrupts the hormonal signals needed for ovulation • Promotes fat storage, especially around the midsection • Increases inflammation • Creates intense carbohydrate cravings (your cells are starving despite high blood sugar)

The weight trap: Insulin resistance makes weight gain easy and weight loss extremely difficult. This isn't willpower — it's biochemistry. "Just eat less and exercise more" doesn't work well when your metabolism is actively working against you.

Key labs for insulin resistance: • Fasting insulin (more sensitive than fasting glucose alone) • HOMA-IR (calculated from fasting glucose and insulin) • HbA1c (3-month blood sugar average) • Fasting glucose

70-80% of people with PCOS have some degree of insulin resistance, including those at a "normal" weight. This is why lean PCOS still responds to insulin-sensitising treatments.