Polycystic Ovary Syndrome (PCOS)

How can a low carbohydrate ketogenic diet help women with polycystic ovary syndrome?

By Dr Laureen Lawlor-Smith, MD

Managing Polycystic Ovary Syndrome (PCOS) with a Ketogenic Diet

Polycystic Ovary Syndrome (PCOS) is an endocrine condition that affects millions of women worldwide and results in approximately one in ten affected women in Australia having difficulty conceiving. The condition affects the ovaries, often leading to various combinations of elevated testosterone levels, irregular or infrequent ovulation and irregular periods. On ultrasound, one or both ovaries may appear enlarged and contain cysts.

PCOS is associated with insulin resistance. The presence of insulin resistance in PCOS escalates the risk of chronic conditions like type 2 diabetes, hypertension, lipid disorders, cardiovascular diseases, and certain cancers such as breast and endometrial cancer. Correcting insulin resistance by reducing dietary carbohydrate intake, has been shown to be beneficial for managing PCOS. The dietary therapy approach should aim to achieve specific objectives, including symptom control, enhancing insulin sensitivity, improved metabolic function, and optimal reproductive health.

Understanding Polycystic Ovary Syndrome (PCOS)

PCOS is a hormonal disorder characterized by imbalanced levels of male reproductive hormones (usually present in women in small amounts), insulin resistance, and multiple small cysts (fluid-filled sacs) on the ovaries. Symptoms can vary widely among individuals but commonly include irregular menstrual cycles, excessive hair growth (hirsutism) on the face or body, acne, weight gain, and infertility. While the exact cause of PCOS remains unclear, factors such as genetics, insulin resistance, and inflammation are believed to play significant roles in its development.

Symptoms of polycystic ovarian syndrome

The Role of a Ketogenic Diet in PCOS Management

A ketogenic diet, characterized by high fat, moderate protein, and very low carbohydrate intake, has gained attention for its potential therapeutic effects in various health conditions, including PCOS. By reducing carbohydrate consumption, the body enters a state of ketosis, where it primarily burns fat for fuel instead of glucose. This state of ketosis can offer several potential benefits for women with PCOS by correcting insulin resistance and reducing inflammation

A ketogenic diet encourages weight loss and reduces fat mass, which leads to decreased insulin secretion after eating, improving insulin sensitivity, and helping glucose tolerance. Adopting a ketogenic diet has been observed to lower androgen levels and restore the balance ratio of luteinizing hormone (LH) to follicle-stimulating hormone (FSH), helping to encourage follicular growth and ovulation.

Ketogenic diet for polycystic ovarian syndrome
Ketogenic diet for polycystic ovarian syndrome

Benefits of a Ketogenic Diet for Women with PCOS

Improved Insulin Sensitivity

Insulin resistance is a notable condition of PCOS, contributing to metabolic dysfunction and weight gain. By reducing carbohydrate intake and consequently lowering blood sugar levels, a ketogenic diet helps mitigate insulin resistance. With improved insulin sensitivity, cells become more receptive to insulin’s actions, leading to better blood sugar control and reduced blood insulin levels. This metabolic shift is crucial for managing PCOS symptoms, as insulin resistance exacerbates hormonal imbalances and contributes to various metabolic disturbances associated with the condition.

Hormonal Balance

PCOS is characterised by imbalanced levels of reproductive hormones, including testosterone, estrogen, and progesterone. Elevated levels of testosterone contribute to symptoms such as hirsutism (excessive hair growth), acne, and irregular menstrual cycles. A study suggests that a ketogenic diet has been shown to influence hormone levels in favour of hormonal balance, as well as reductions in testosterone levels in women6, thereby reducing symptoms such as hirsutism and acne. By restoring hormonal balance, ketosis helps regulate menstrual cycles and improve fertility outcomes for women with PCOS.

Weight Management

Weight gain and obesity are common concerns for women with PCOS, further increasing metabolic dysfunction and hormonal imbalances. A ketogenic diet promotes weight loss and aids in weight management through several mechanisms. Firstly, the high protein content of the diet induces a feeling of satiety, reducing overall calorie intake and promoting adherence to the dietary regimen. Secondly, ketosis enhances fat oxidation and metabolism, leading to increased fat loss compared to traditional low-fat diets. Additionally, the stabilising effect of ketosis on blood sugar levels helps prevent spikes and crashes in energy, reducing cravings and binge eating behaviours commonly associated with PCOS.

Reduced Inflammation

Chronic inflammation has been implicated in the pathogenesis of PCOS and contributes to its associated complications, including insulin resistance, ovarian dysfunction, and cardiovascular risk. Ketogenic diets have been shown to exert anti-inflammatory effects, largely through the inhibition of pro-inflammatory signalling pathways and the production of inflammatory mediators. By reducing systemic inflammation, ketosis helps alleviate symptoms and improve overall health outcomes in women with PCOS.

Enhanced Fertility

Infertility is a significant concern for women with PCOS, often attributed to irregular ovulation and hormonal imbalances. By reducing insulin resistance, and restoring hormonal balance and ovulation, the ketogenic diet leads to improved fertility outcomes.

Polycystic ovarian syndrome treatment with ketogenic diet

Scientific Evidence Supporting Ketogenic Diet for PCOS

Numerous scientific studies have explored the efficacy of a ketogenic diet in managing PCOS symptoms:


A ketogenic diet holds enormous potential as a therapeutic intervention for women with PCOS, offering many benefits ranging from weight management and improved fertility to hormonal balance and metabolic health. While further research is warranted to clarify the long-term effects and optimal dietary strategies, the existing evidence highlights the transformative impact of low-carbohydrate diets in alleviating the burden of PCOS. By embracing a ketogenic lifestyle, individuals with PCOS can embark on a journey towards improving their quality of life naturally.