How common is PCOS?
The World Health Organization estimates that between 8 and 13 percent of women of reproductive age have PCOS, and up to 70 percent of those affected are undiagnosed. It is one of the most frequent causes of irregular cycles and of difficulty ovulating.
How insulin drives it
Most women with PCOS have some degree of insulin resistance. The 2023 international guideline notes that it occurs in the majority, and that it occurs in lean women as well as those with higher body weight. The mechanism works like this:
- High insulin acts on the ovaries and stimulates them to produce more androgens, the so-called male hormones such as testosterone.
- High insulin lowers sex hormone binding globulin (SHBG) in the liver. With less SHBG, more testosterone is free and active.
- Excess androgens interfere with ovulation, which leads to irregular periods and small follicles on the ovary. They also cause acne, scalp hair thinning and extra facial or body hair.
- Insulin resistance makes weight gain around the middle easier, and abdominal fat in turn deepens the resistance.
It is a loop, and the loop is why lifestyle changes that improve insulin sensitivity often improve PCOS symptoms.
How PCOS is diagnosed
Doctors diagnose PCOS in adults when two of three features are present, after other causes are ruled out: irregular or absent ovulation, signs of high androgens (on examination or on blood tests), and a polycystic appearance of the ovaries on ultrasound or a high anti-Müllerian hormone level. If you suspect PCOS, ask your doctor about a full assessment that also includes a glucose test and a lipid panel.
What the evidence supports
The international guideline puts lifestyle first: a healthy diet, regular physical activity and, for those who need it, modest weight loss. It does not name one best diet. Eating plans that lower the glycemic load, such as Mediterranean-style eating with plenty of legumes, vegetables, whole grains, fish and olive oil, are reasonable and well tolerated. Metformin can be considered, especially for women with higher body weight, and your doctor can discuss it. Inositol supplements are popular, but the guideline considers the evidence still limited, so treat them as something to discuss, not assume.
Kitchen strategies that fit PCOS
- Eat protein and fiber at breakfast. A carbohydrate-only breakfast tends to set up a glucose and insulin spike early in the day. Try the spinach, white bean and egg bake, which you can make on Sunday and eat all week.
- Use lentils for body and bulk. The red lentil and walnut bolognese is rich, slow-digesting and freezes well.
- Keep anti-inflammatory fats in play. Olive oil, walnuts and oily fish are good fits.
- Do not under-eat. Very low-calorie diets can worsen cycle irregularity and trigger rebound eating. Steady meals work better.
- Lift weights. Muscle improves insulin sensitivity and does not depend on body weight changing.
Talk to your doctor before starting supplements or medicines. Many PCOS treatments are not suitable in pregnancy, and ovulation can return as insulin sensitivity improves.
PCOS also raises the long-term risk of type 2 diabetes, fatty liver and heart disease, so it deserves regular checks. See insulin resistance and prediabetes for glucose targets.
Spinach, White Bean and Egg Breakfast Bake
A sweet or starch-only breakfast often leads to a mid-morning crash.
Red Lentil and Walnut Bolognese
You can eat spaghetti with insulin resistance.
Quick recipes for PCOS
Every recipe below takes 30 minutes or less and is built around fiber, protein and slow carbohydrate. Browse the full recipe collection for more.
- Spinach White Bean Skillet Egg Bake (20 Minutes) (20 min): Many people with PCOS are told to avoid high-sugar breakfasts such as cereal, pastries and juice.
- Red Lentil Walnut Bolognese (25 Minutes) (25 min): You can eat spaghetti with insulin resistance and PCOS.
- Tofu Tomato Ginger Soup with Edamame (20 Minutes) (20 min): Soy foods such as tofu and edamame are good sources of protein and, according to several reviews, are not harmful for people with PCOS when
- Quick Coconut Chicken and Chickpea Curry (25 min): Curry has a reputation for taking hours, but chicken pieces cook through in 10 minutes.
- Zucchini Ribbon Salad with Chicken and Goat Cheese (15 min): A salad is only useful if it keeps you full.
- Cottage Cheese Berry Chia Bowl (5 Minutes) (5 min): Breakfast is where many people with PCOS struggle, because the quick options are usually sugary.
References
- Teede HJ, et al. Recommendations from the 2023 international evidence-based guideline for the assessment and management of polycystic ovary syndrome. Fertil Steril 2023;120:767-793.
- Diamanti-Kandarakis E, Dunaif A. Insulin resistance and the polycystic ovary syndrome revisited. Endocr Rev 2012;33:981-1030.
- World Health Organization. Polycystic ovary syndrome fact sheet.
Please note. This page is for education and is not medical advice. If you take insulin or medication that can cause low blood sugar, such as a sulfonylurea, talk to your care team before making large changes to what you eat. Read our medical disclaimer.