PCOS: Diet, Lifestyle and Supplements

This article discusses

  • What is PCOS?
  • Diet and Lifestyle Recommendations for PCOS
  • PCOS and Supplements
  • A quick word on PCOS and misinformation

​​​​​​​What is Polycystic Ovary Syndrome (PCOS)?

PCOS is a complex endocrine (hormonal) condition that affects 8-13% of women of child-bearing age. PCOS is often driven by higher-than-normal levels of “male hormones”, known as androgens, in women.

What causes PCOS

The exact cause of PCOS is not known, however, a combination of lifestyle and genetics appears to play a role. If your mother has PCOS, your risk of having PCOS increases. It is widely accepted that insulin resistance, increased levels of insulin and androgens drive PCOS.


Insulin is the hormone that allows glucose (the sugar that your body uses for energy) to enter your cells. If you become insulin resistant (as is the case for many PCOS women), it means your insulin is not working as well. To compensate (i.e., drive glucose into your cells), your body produces even more insulin.


This increase in insulin drives your ovaries to more testosterone than needed, which causes many of the symptoms observed in PCOS


The hormonal changes observed in PCOS lead to are several symptoms that can affect various body systems.

Hair, Skin and Body: Excessive body hair (hirsutism), acne, male pattern baldness, weight gain and difficulty losing weight

Periods and fertility: Irregular, infrequent or no periods, multiple follicles on your ovaries, difficulty becoming pregnant and increased risk of complications (however, having PCOS doesn’t make you infertile)

Psychological health: mood changes, increased risk of anxiety and depression, lower self-esteem, disordered eating

Long term health conditions

Regardless of BMI, ethnicity, or age, PCOS can increase your risk of some long-term health conditions such as

  • Diabetes: Prediabetes, Type 2 Diabetes and Gestational diabetes
  • Heart disease
  • High Blood Pressure
  • Sleep Apnoea
  • Endometrial cancer

It is important to note that you may only experience a handful of symptoms and the symptoms experienced will differ from person to person. Having PCOS can be a challenging experience. However, with an accurate diagnosis and appropriate support from your GP and other clinicians such as dietitians, psychologists, both the short- and long-term symptoms of PCOS can be managed.


The diagnosis of PCOS is quite complex

You require to meet 2 of the 3 criteria to be diagnosed with PCOS

  1. Irregular periods or no periods
  2. High levels of testosterone shown by
    • Blood test AND/OR
    • Symptoms of excess body or facial hair, acne, hair loss from the scalp (that follows male pattern hair loss)
  3. Ovaries with multiple follicles visible on ultrasound (only if you have had periods for 8 years or more). (Despite the name polycystic ovary syndrome, they are follicles, not cysts. Furthermore, not every PCOS patient will have these follicles)

Other conditions can cause similar symptoms to PCOS, so your doctor must exclude these before a PCOS diagnosis is made.

A Note on PCOS & Fertility

There is a common myth that PCOS makes you infertile. While PCOS can make it harder to become pregnant, a healthy lifestyle and medical support will allow most women with PCOS to have children.

  • 30% of PCOS women have no problems getting pregnant
  • 70% of PCOS women may experience difficulties becoming pregnant, however, most women with the appropriate support can become pregnant

For more info on PCOS and fertility, click here.

PCOS and Diet

According to PCOS management guidelines, nutrition and lifestyle often play the most important role in PCOS management and should be discussed as the first line of treatment (before medications are introduced).

The healthy eating guidelines recommended to the general public also apply to the management of PCOS. Here is the Healthy Plate Model, aim for most of your meals to look like this:

For further information about portion sizes, click here

Women with PCOS should consider:

  • Low Glycaemic Index (Low GI) Carbohydrates
  • Protein
  • Healthy fats
  • Meal timing

Low glycaemic (Low GI) carbohydrates

Low GI carbohydrates cause a slower increase in your blood sugar levels. This means they help balance insulin levels which has been shown by research to reduce PCOS symptoms.

Minimally processed and high fibre carbohydrates are typically the ones that have a low GI. Examples of low GI carbohydrates include:

  • Wholegrain bread
  • Sweet potato
  • Chickpeas
  • Lentils
  • Apples
  • Oats

Paying attention to the portion sizes of your carbs and pairing them with lean protein and healthy fats will help balance your blood sugar and insulin further. It is important to note that a low GI diet does not mean a low carbohydrate diet.  Choosing low GI carbohydrates means that you can still enjoy carbohydrates whilst managing your PCOS symptoms.


Including sufficient protein in our meals and snacks can help us

  • Feel satisfied and fuller for longer
  • Balance our blood sugar

There is also evidence suggesting that including plant-based sources of protein (e.g., chickpeas, edamame) is associated with better fertility rates (Panth et al., 2018).

Healthy fats

Using healthy fats is important in the management of PCOS.

Examples of foods that provide healthy fats are

  • Extra virgin olive oil
  • Avocado
  • Nuts and seeds
  • Oily fish (a good source of protein and omega-3 fats)

Meal timing

Spreading your meals and snacks throughout the day (that is, eating roughly every 3-4 hours) can help balance your blood sugar and insulin levels. This means eating 3 meals (breakfast, lunch, and dinner) and 2 snacks in between for most people. Here is an example of a day of eating:

Breakfast: 2 scrambled eggs with 2 slices of wholegrain bread topped with hummus

Morning Tea: 1 apple with 2 tbs peanut butter

Lunch: Slice of frittata with a side salad dressed with olive oil, lemon and salt and pepper

Afternoon Tea: Pottle of yoghurt with a handful of nuts

Dinner: Vegetable and tofu dahl with brown rice (recipe for lentil dahl here)

PCOS and weight loss

Research has found that a 5-10% weight loss (in those who were overweight) reduces the levels of male hormones being produced by the body and improves the body’s ability to use insulin. This has been shown to

  • Improve many PCOS symptoms, e.g., period regularity, excessive hair growth
  • Improve fertility

If you seek weight loss, focus on having nutritionally balanced and healthy meals and take a slower sustainable approach (losing 0.5-1kg a week, or even less if you don’t have much weight to lose). Doing it this way gives you time to form some long-lasting habits and means that you are less likely to regain the weight that you have lost.

However, improving the nutrition of your diet, moving more, finding stress management strategies, and better sleep can still improve your PCOS symptoms even if you don’t lose weight. Note that weight loss in healthy weight individuals is not recommended as it does not improve PCOS symptoms. Note that yo-yo dieting (going on and off diets) is damaging to long term health. If you have a history of yo-yo dieting, it is recommended that you speak to a Registered Dietitian or Registered Nutritionist.

PCOS and eating disorders

There is a higher rate of eating disorders in PCOS. If you struggle with binge eating or heavily rely on food as a coping tool, it is recommended that you connect with a Registered Dietitian and Psychologist.

PCOS and Lifestyle Factors

Nutrition is just one piece of the puzzle. It is also important to consider

Stress management: Having PCOS can be stressful, and unfortunately, stress has been found to worsen PCOS symptoms (Papalou & Diamanti-Kandarakis, 2016). Therefore, self-care and finding stress management strategies are absolute essentials in PCOS management.

Movement and physical activity: Amongst a range of benefits, physical activity helps improve insulin sensitivity. Find a type of activity you enjoy. This could be dancing, running, online fitness classes etc. It is recommended that adults get 30 mins/day of moderate-intensity exercise a day or 150 min/week.

Sleep: Fatigue is a common symptom in PCOS and PCOS put you at higher risk for sleep apnoea. Women with PCOS need consistent sleep to feel energized. The general recommendation is to get between 7-9 hours every night and sleep and wake up at roughly the same time each day.

PCOS and Supplements

There is emerging research that certain supplements in addition to a nutritious and balanced diet may help with the management of PCOS symptoms. However, more research is needed before we can make any firm recommendations.

Tips for PCOS and supplementation

  • Focus on first optimizing your diet and then consider supplementation.
  • If you are considering any supplement (in this list or otherwise), consult your doctor and/or dietitian. It is ideal to work with a practitioner who has expertise in PCOS and supplementation.
  • Ideally, you would get blood tests done (if a blood test is available for that nutrient) to assess your baseline levels (and check whether you are deficient) and then later on to evaluate the impact of the supplement


Inositols are small molecules naturally found in foods like whole grains and citrus fruits. Some research has found that inositol supplementation helped with

  • Insulin sensitivity
  • Regulating cycles

Inositols are perhaps the most widely researched PCOS supplements.  Most research has used between 2-4mg/day of inositol, with no reported side effects. Side effects such as nausea typically occurred at 12g/day. Some research suggests that taking Myo-inositol and D-chiro-inositol in a 40:1 ratio is most beneficial (Nordio et al., 2019).

Vitamin B12

Some women with PCOS may be prescribed metformin, a drug that improves insulin sensitivity. However, according to the international PCOS guidelines, long term use of metformin has been associated with low Vitamin B12 levels, and they encourage monitoring of B12 levels. In this patient group, a B12 supplement may be beneficial.


Limited evidence suggests that an omega-3 supplement helps improve insulin resistance and improved blood lipids (Yang et al., 2018).

Vitamin D

A vitamin D deficiency is common in women with PCOS, likely because vitamin D plays a role in hormonal health and insulin sensitivity. If you have darker skin or don’t get sun exposure, you are at an even higher risk of deficiency. Speak to your doctor about vitamin D supplementation.


Magnesium deficiency is common in women with PCOS (Babapour et al., 2021). Consider getting a blood test to assess for magnesium deficiency before supplementation.

PCOS and Misinformation

While several evidence-based websites provide helpful advice on PCOS management (listed below), many others spread nutrition misinformation. Red flags to look out for are

  • Sources that recommend all women with PCOS to cut out dairy, gluten and soy
    • The only people required to cut out these foods are those who are allergic to them or those with coeliac disease (can’t have gluten)
    • If you feel that you are intolerant to any of these foods, it is worth talking to your doctor or dietitian to conduct further investigations
  • Broad recommendations to use keto
    • Currently, there are only two trials on the use of keto for PCOS management- both had very few people participating in the studies (Mavropoulos et al., 2005 and Paoli et al, 2020). While there were some positive results, due to the restrictive nature of the keto diet we would need larger studies with much larger participant groups before we could make any sort of broad recommendations.

Look for content written by:

  • Reputable health, government and university organisations
  • Registered Dietitians and Registered Nutritionists (note, not all nutritionists are registered, look for ones who are)

Working with professionals

If you are diagnosed with PCOS, it is essential to be working with a supportive GP who

  • understands that nutrition and lifestyle is the first line of management and uses medication where appropriate
  • has a long term plan for managing your PCOS and conducts timely check-ups. Once every 1-2 years if your PCOS is well managed, more if your symptoms are not well managed
  • Connects you to, e.g., a dietitian, psychologist, where appropriate

If you feel that you require extra support, don’t be afraid to ask your GP for it.

More information:


Associations Between Serum Magnesium Concentrations and Polycystic Ovary Syndrome Status: a Systematic Review and Meta-analysis. Biological Trace Element Research, 199(4), 1297-1305.

Mavropoulos, J. C., Yancy, W. S., Hepburn, J., & Westman, E. C. (2005). The effects of a low-carbohydrate, ketogenic diet on the polycystic ovary syndrome: A pilot study. Nutrition & Metabolism, 2(1), 35.

Nordio, M., Basciani, S., & Camajani, E. (2019). The 40:1 myo-inositol/D-chiro-inositol plasma ratio is able to restore ovulation in PCOS patients: comparison with other ratios. Eur Rev Med Pharmacol Sci, 23(12), 5512-5521.

Panth, N., Gavarkovs, A., Tamez, M., & Mattei, J. (2018). The Influence of Diet on Fertility and the Implications for Public Health Nutrition in the United States. Frontiers in public health, 6, 211-211.

Paoli, A., Mancin, L., Giacona, M. C., Bianco, A., & Caprio, M. (2020). Effects of a ketogenic diet in overweight women with polycystic ovary syndrome. Journal of translational medicine, 18(1), 104.

Papalou, O., & Diamanti-Kandarakis, E. (2017). The role of stress in PCOS. Expert Review of Endocrinology & Metabolism, 12(1), 87-95.

Yang, K., Zeng, L., Bao, T., & Ge, J. (2018). Effectiveness of Omega-3 fatty acid for polycystic ovary syndrome: a systematic review and meta-analysis. Reproductive Biology and Endocrinology, 16(1), 27.


Last modified: June 22, 2022