Mediterranean-style diets are high in dietary fiber, antioxidants, polyphenols, and anti-inflammatory nutrients, and while there isn’t a “PCOS Diet,” current recommendations align with the Mediterranean Diet. For example, a healthful PCOS diet should focus on unprocessed, fiber-rich foods and include the following foods: fatty fish, dark leafy greens, dark red fruits and berries, cruciferous vegetables, legumes, healthy fats in moderation, nuts, and spices. Additionally, women with PCOS may experience long-lasting, low-grade chronic inflammation, making it essential to consider anti-inflammatory foods. An anti-inflammatory diet may benefit PCOS and includes foods known to reduce inflammation-related symptoms, such as fatty fish, leafy greens, berries, and extra virgin olive oil.

The Western diet may increase the metabolic risk factors associated with PCOS, including low-grade inflammation, hyperandrogenism, hyperinsulinemia, and an unhealthy diet. Additionally, it may negatively impact female fertility. The Western diet is rich in pro-inflammatory foods found, which should be avoided by those with PCOS. This includes added sugars, trans-fats, processed meats such as sausages, luncheon meats, and hot dogs; refined carbohydrates including pastries and white bread; fried and fast food; and solid fats including shortening, lard, and margarine. Moreover, diets rich in animal proteins are associated with an increased risk of ovulatory infertility. In contrast, vegetable protein intake is associated with a lower risk of ovulatory infertility.

Modest weight loss of 5-10% in women with PCOS can improve endocrine and reproductive function. In addition, weight loss can improve insulin resistance, androgen concentrations, menstrual cycle cyclicity and ovulatory function, hyperlipidemia, reduce the risk of type 2 diabetes and cardiovascular disease, and improve the overall quality of life. Weight loss can be achieved through moderate-intensity physical activity of 30 minutes or more most days of the week and strength training to increase muscle mass twice a week. Weight loss is better achieved when combined with a healthy diet. If weight loss is necessary, personalized recommendations may be provided by a qualified practitioner. Find a practitioner to learn more.

A personalized diet that considers energy intake, energy restriction if weight loss is needed, and nutrient composition to improve insulin resistance, metabolic function, and reproductive function is recommended for PCOS. Nutritional recommendations should consider individual preferences, dietary habits, culture, and metabolic needs. The nutrient composition should be a primary focus because it can affect insulin sensitivity regardless of weight loss. In addition to reducing IR, dietary intervention can improve insulin resistance, reproductive dysfunction, help with weight management, and regulate insulin levels. See a healthy PCOS sample diet below. A personalized diet may be provided by a qualified practitioner. Find a practitioner to learn more.

Diets rich in fiber and complex carbohydrates are associated with greater insulin sensitivity, delayed gastric emptying, and increased satiety. In addition, plant sources of dietary fiber such as fruits, vegetables, legumes, and whole grains encourage glycemic control and provide beneficial phytochemicals such as polyphenols, which have demonstrated improvements in insulin secretion, insulin sensitivity, and decreased hyperglycemia. Moreover, a high-fiber diet may benefit PCOS because of its relationship with gut microbiota, releasing short-chain fatty acids (SCFAs) that reduce chronic inflammation and maintain the intestinal barrier.

Low-glycemic foods are beneficial for women with PCOS and may improve insulin sensitivity, insulin resistance, decrease inflammation, and improve ovulatory cycles in women with anovulatory PCOS. A low glycemic index (GI) diet includes carbohydrates from low-GI foods, including fruits, vegetables, whole grains, legumes, nuts, and seeds. These foods are more slowly digested, absorbed, and metabolized. By slowing digestion, low GI foods help regulate insulin levels. Conversely, high-GI foods cause increased blood glucose concentrations and a higher demand for insulin production. Thus, high-GI diets may increase insulin resistance.

Meal timing and eating patterns are essential aspects of dietary intervention in women with PCOS. First, eating small, frequent meals throughout the day, about four to six meals or snacks daily, is recommended for PCOS. For example, a six-meal eating pattern may improve insulin sensitivity, fasting insulin levels, and reduce hunger in women with PCOS. Additionally, carbohydrate intake should be spread out throughout the day. Focusing on complex fiber-rich carbohydrates is recommended. Another important dietary habit for PCOS is eating breakfast and not skipping meals. Additionally, lean protein should be included in all meals and snacks, such as lean meats, fish, tofu, lentils, beans, nut butters, and low-fat dairy products.

Inositols such as myo-inositol and d-chiro-inositol are found in high-fiber foods such as beans, legumes, fruits, and vegetables. Inositols have shown a protective role in the pathogenesis of metabolic diseases. Additionally, they serve as secondary messengers for insulin. An imbalance or deficiency of inositols contributes to various characteristics of PCOS, including androgenic, metabolic, ovulatory, and menstrual features. Inositols may benefit PCOS by improving the LH to FSH ratio, ovarian function, and metabolism. Additionally, it may help decrease insulin resistance and BMI. Inositol may impact female fertility by enhancing the development of ovarian follicles, oocyte maturation, and stimulation of pregnancy with in vitro fertilization (IVF).

Anti-Mullerian hormone (AMH) is essential for folliculogenesis and serves as an ovarian biomarker. Elevated levels of (AMH), secreted by the granulosa cells of preantral and small antral ovarian follicles, are regularly observed in women with PCOS. Vitamin D is essential for hormone synthesis, including progesterone, LH, and FSH, through AMH signaling. In women with anovulatory PCOS, vitamin D supplementation may decrease AMH, although evidence is conflicting with supplement recommendations. Thus, maintaining adequate vitamin D is essential.

Anti-androgen foods may benefit PCOS by reducing testosterone levels, while flavonoids such as quercetin and resveratrol may reduce androgen synthesis and improve hyperandrogenism. For example, soybean has phytoestrogens and isoflavones with androgen modulating capabilities. Resveratrol is a polyphenol found in red wine, berries, and grapes. Additionally, polyphenols may have a role in preventing PCOS, slowing the progression of inflammation, improving insulin sensitivity, and compensatory hyperinsulinemia. The Mediterranean diet is high in plant polyphenols from fruits, vegetables, legumes, grains, nuts, seeds, extra-virgin olive oil, and red wine. Lastly, green tea may lower testosterone levels and promote insulin sensitivity in women with PCOS.