Polycystic ovaries syndrome (PCOS) affects millions of women worldwide, with an estimated prevalence of 1 in 10 women in the UK1,2. It is an endocrine syndrome which can cause problems to our menstrual cycle and fertility3,4. While we cannot cure PCOS, dietary and lifestyle changes can help relieve the symptoms1,5.
Periods and premenstrual syndrome (PMS).
Periods are part of the menstrual cycle and most women have one approximately every 28 days. They usually start around puberty, anywhere from the age of 12, with most girls having regular periods by the age of 16 to 186.
Being underweight, having an eating disorder, having a hormonal imbalance or problems with the ovaries can all influence periods7.
Up to 80% of women experience physical, psychological or behavioural changes including changes in our appetites before our periods. This is recognised as PMS8,9.
PCOS is a common condition which effects women’s hormones, periods and fertility2,10.
While the exact cause is unknown it seems to be related to our genetics, as it tends to run in families and is associated with an imbalance in hormones2,11. Other distinctive features of PCOS include: chronic anovulation (where our ovaries do not release an oocyte, an immature egg, during the menstrual cycle) and the presence of high androgen levels2, 11, 12.
It is common for PCOS to go undiagnosed; an estimated 68-69% of women with PCOS go without a diagnosis13. This may be because more than half of women with PCOS do not have any symptoms2.
PCOS symptoms can include 2,11:
• Irregular or no periods.
• Excessive hair in places it is not normally found, including face, chest or stomach.
• Thinning hair on the head
• Difficulty maintaining a healthy body weight
• Fertility problems
How is PCOS diagnosed 2,5,11?
The presence of two of the following three criteria is often enough for a health care professional to diagnose PCOS:
1. The presence of several fluid-filled sacs which surround the eggs in our ovaries
2. Eggs being irregularly released from our ovaries
3. Increased activity or increased amount of the hormone group androgens (including testosterone and androstenedione)
Eating behaviours associated with PCOS
Binge eating behaviours have been associated with women who have PCOS11 with 39% of women with diagnosed PCOS showing binge eating behaviour compared to 24-32% in matched controls without PCOS14.
Food cravings also may be linked to PCOS as described in anecdotal evidence although this is less clear due to research limitations14.
Eating disorders are a serious mental illness and include binge eating disorder. For support with eating disorders, the Beat Eating Disorders Charity helplines and website are available to us15.
Dietary Recommendations for women with PCOS
A balanced diet
Eating a balanced diet whilst keeping active can help to improve the symptoms of PCOS2. For women with PCOS it is recommended especially to eat lots of fruits and vegetables while limiting our intake of foods and drinks high in fat and sugar11.
A balanced diet includes16:
• Basing meals on a high fibre starchy food
• Eating five portions of fruit and vegetables a day
• Eating some protein
• Eating some dairy or alternative
• Choosing unsaturated fats (in small amounts) over saturated fats
• Drinking six to eight glasses of water a day
Low glycaemic index diet
Consumption of certain carbohydrates have been shown to affect PCOS symptoms therefore controlling this may help to manage the symptoms of PCOS17.
These types relate to their glycaemic index (GI). GI is a relative ranking system of carbohydrate foods. It relates to how quickly they raise our blood sugars after consumption11.
Low GI foods are ones which cause our blood sugar levels to raise slowly. High GI foods are ones which cause our blood sugar levels to raise quickly11,18,19.
Consumption of low GI foods can help to reduce the symptoms of PCOS11,18,19.
Low and medium GI foods are often high in fibre and include20:
• Fruit and vegetables
• Pulses including beans and lentils
• Wholegrains including oats and rye bread
High GI foods include are often refined carbohydrates and include20:
• White bread and rice
• Sugar sweetened beverages
It is important to note that having PCOS, does not mean we cannot eat foods with a high GI. Eating them just means PCOS symptoms may be worse.
For more information about glycaemic index, visit the “What is the glycaemic index (GI)?” page on the NHS website20.
Weight management and movement
Being overweight has been shown to potentially worsen the symptoms of PCOS. A safe and small amount of weight loss may be recommended, of 0.5-2 pounds per week11, as it can have significant improvements on the symptoms of PCOS11,21.
A really important thing to consider is finding something which fits in to our everyday life, is enjoyable and to still consume a balanced diet with all the nutrients we need. Exercising has been shown to help PCOS symptoms11. Talk with your GP or a registered dietitian for support.
Fertility and PCOS
It is important to consume a balanced diet and all the nutrients we require when trying for a baby. A folic acid supplement is often recommended11. Talk to your GP or registered dietitian to find out more about this and specific nutrition to you and your fertility journey.
Dietary and Lifestyle advice for managing the symptoms of PCOS.
1. Eating a balanced, varied diet
2. Consider swapping some GI foods with low or medium GI options
3. Increasing movement
4. Talk to your GP, a registered nutritionist or dietitian
Resources to help us
• The National Health Service. Polycystic Ovary Syndrome2
• The British Dietetics Association. Glycaemic Index (GI): Food Fact Sheet22
• Verity. A self-help group for women with PCOS23
While there is currently no cure for PCOS, the are several lifestyle adjustments we can make to reduce our symptoms. There are also medicines available to help with PCOS symptoms, so talking to a GP may help.
This blog post was written by Emilia Fish, a Food Science and Nutrition graduate and soon-to-be MSc Clinical and Public Health Nutrition student at UCL. She is part of the Nutrition Rocks intern team and enjoys sharing simple, evidence-based nutrition on @nutritionnourishment. Emilia has recently launched a podcast: Journeys in Food, Nutrition and Sustainability.
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