Nutrition for PCOS: A Dietitian’s Guide

Nutrition for PCOS

Polycystic Ovarian Syndrome (PCOS) is a common hormonal condition that affects 1 in 10 women. For women of reproductive age, it affects 12-18% of individuals, although reportedly up to 70% of women with the condition remain undiagnosed.

Polycystic literally means “many cysts.” Ovarian means it is in the ovaries. Therefore, PCOS stands for many cysts within the ovaries.

Polycystic ovarian syndrome diagram

Even though that is the translation, the diagnosis doesn’t rely on there being cysts. Some women may not even have cysts in their ovaries since the diagnosis involves having any two of these three factors:

  1. Lack of ovulation causing irregular menstrual cycles (either <21 days apart, >35 days apart or no cycle at all).
  2. Excess male hormone production (e.g. testosterone) detected through a blood test.
  3. Cysts on the ovaries as detected via ultrasound.

Other symptoms can include: hair growth/loss, skin changes (e.g. acne or darkening of the skin), weight gain, anxiety, depression, sleep apnoea and difficulty conceiving.

It also increases the risk of certain conditions including type 2 diabetes, cardiovascular disease and endometrial cancer.

There is no cure for PCOS, but there are lifestyle steps that you can take that can help manage the symptoms.

Insulin Resistance

Link between insulin resistance and PCOS

Around 85% of women with PCOS also experience insulin resistance with the numbers being slightly skewed based on other factors e.g. those who are lean are slightly less likely to have insulin resistance.

This insulin resistance is part of why the risk of type 2 diabetes is increased. The body is less able to remove glucose from the blood, which leads to higher insulin levels and potentially higher blood glucose levels as well.

A lot of the steps in managing PCOS involve attempting to reduce insulin resistance or the effects of it.

Overall Healthy Diet

Fresh vegetables, fruits, and nuts on gray background

The first step before going into specifics is to aim for an overall healthy diet. Consume a wide variety of nutritious foods with an emphasis on fruits, vegetables and lean protein sources. A lot of other general rules for a healthy diet also will apply to nutrition for PCOS as well.

Weight Management

Healthy high fibre plant-based food

Weight-loss can be beneficial for PCOS under a lot of circumstances. While lean PCOS does exist (and a lot of the other nutritional strategies will be beneficial for that), if somebody is carrying more body fat than ideal, weight-loss could help manage the symptoms of PCOS.

Using insulin resistance specifically as an example, decreases in body fat have consistently been strongly linked with decreases in insulin resistance for those with PCOS.

Decreasing Carbohydrate Intake

Lower carb healthy meal

While a low carbohydrate diet can work very well, there are also still nutritional advantages from keeping carbs in the diet. Good quality carbohydrate sources can add fibre, micronutrients and beyond that, they can also help from a quality of life perspective; let’s be realistic, most people like carbs.

That being said, I would still recommend avoiding consuming an excessive amount of carbohydrates. All carbohydrates break down into glucose in the blood, which requires insulin to be utilised to take the excess glucose out of the blood. This is a more difficult job with insulin resistance.

Beyond that, carbohydrates contain calories, just like protein and fats do. Decreasing carbohydrate intake is also decreasing calorie intake unless it is replaced with more fats and proteins. Creating a calorie deficit is the key to getting leaner.

Taking this a step further, a ketogenic diet has small-scale evidence that it can help reduce symptoms through helping to reduce body weight (due to the calorie deficit that is typically created), improvements in hormone levels and a significant reduction in insulin levels.

One reason why I’m hesitant to recommend even a well-structured ketogenic diet that addresses most of the nutrients that are often lacking is that sticking with it is quite difficult. In the research that has been done so far, compliance is quite low over the long term and carbohydrate intake typically increases over time until the average intake is well above the range required to stay in ketosis. For some individuals, this isn’t an issue, but for the majority it is.

Aim for Lower GI Carbohydrates

Glycaemic Index

Aiming for lower GI carbohydrates as your main carbohydrate sources can help as well. Beyond directly helping to manage insulin resistance, this has been shown to reduce the risk of complications down the line such as endometrial cancer.

Anti-Inflammatory Style Diet

Anti-Inflammatory foods for PCOS

Dietary approaches that are high in monounsaturated fats, omega 3’s, fibre and antioxidants seem to help manage the symptoms of PCOS as well.

For example, a Mediterranean diet has been frequently studied for PCOS with positive outcomes. This style of diet is high in vegetables, fruits, legumes, wholegrains, fish, poultry and healthy fats such as extra virgin olive oil, avocado, nuts and salmon.

In addition to the main symptoms of PCOS, this dietary pattern has been strongly linked with reduced symptoms of anxiety and depression.


High antioxidant anti-inflammatory foods

PCOS features a lot of symptoms linked with oxidative stress. There also appears to be reduced levels of antioxidants and overall nutrient levels in women with PCOS. Increased antioxidant intake, in general, appears to help manage symptoms of PCOS.

I’m typically cautious with antioxidant supplementation, since oxidative stress is still a vital process in a lot of the body’s functions. Whenever studies involve increasing antioxidant intake through food, there are typically no downsides. Sometimes downsides appear when high dosages of supplements are used for the same purposes though.

That being said, there is a study showing reductions in testosterone and insulin resistance in those who took resveratrol supplements.


Speaking of supplements, while the priority should be on meeting nutrient needs through food first where possible, I have also written a blog post specifically on supplements that can help.

The short version of it is that some supplements can have potential benefits under certain circumstances. Ones that could be worth looking into include inositol, magnesium, omega 3’s, cinnamon, chromium and vitamin D. The potential benefits of those supplements and a few more are broken down in that post.


Although PCOS isn’t curable, taking these steps among other things could significantly reduce the symptoms associated with PCOS. There are many different nutritional strategies that can be utilised, but these tips mentioned are likely to help significantly if implemented.

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