Polycystic Ovarian Syndrome (PCOS) and Nutrition
Written by: Maia Lockhart, RDN
Reviewed by: Dr. Rose Abbott
What is PCOS?
PCOS is one of the most common endocrine disorders, affecting nearly one in ten women of reproductive age in the UK. And despite being more common than diabetes, many women haven’t even heard of the condition. This might be because PCOS can present differently in different people and is a multifaceted disorder with diverse clinical implications.
Lack of periods or irregular periods
Hirsutism (excess hair generally on the face, chest and stomach)
Difficulty losing weight / ease gaining weight
Mood changes, depression and anxiety
It can take up to two years for the condition to be diagnosed, because symptoms often aren’t taken seriously enough or are confused with other conditions. Diagnostic criteria are still developing, but currently women are often diagnosed via something called the Rotterdam Criteria. This criteria states that for PCOS to be identified, two of the following must be present:
Irregular periods or no periods
Excess circulating androgens, with or without physical signs such as acne, excess weight, excess hair (this can be found with a blood test)
Polycystic ovaries (identified with an ultrasound scan)
PCOS is complex, and as it often presents itself in different ways for different women, it can be difficult to recognise immediately. It can be helpful to learn about this diagnosis early. With correct management, it is possible to reduce potential complications such as glucose impairment leading to type 2 diabetes, cardiovascular disease, fertility issues, pregnancy complications, endometrial hyperplasia (that could be a risk factor for cancer of the uterus / womb) and its impact on mental health.
Management should focus on reducing these risks through lifestyle measures and monitoring (specifically weight, blood sugar and blood pressure control, avoiding smoking and alcohol excess). Currently the limited prescribed medication options for PCOS include cyclical progesterone, several types of combined oral contraceptive pills, the Mirena IntraUterine Device (hormonal / progesterone coil) and in some cases, under specialist supervision such as a fertility clinic, the use of medications such as Metformin and Clomifene (Clomid).
Can nutrition help?
Whilst there is no known cure and the same things don’t always work for everyone, nutrition has been shown to greatly improve symptoms for those living with the condition. Insulin is a hormone made in the pancreas, and it helps to move sugars in the blood into the body’s cells so that it can be utilised for energy. Up to 80% of those living with PCOS are insulin resistant, meaning there is often too much circulating glucose and this has the potential for pre-diabetes. This is often the reason for tiredness and sluggishness in PCOS.
Although you may have heard of catchy news headlines such as ‘The benefits of Keto for PCOS’ or ‘Cut dairy for PCOS’, there is unfortunately no one ‘best’ way of eating for PCOS management. However, there are a few things that have been found to be helpful in managing symptoms in some women.
Insulin and blood sugar control
It is important to consider the type of carbohydrate you are eating. There is a thing called the ‘glycaemic index’ (GI) and this is basically a way of rating different foods containing carbohydrates, because not all carbohydrates affect the body in the same way. Some carbohydrates cause a more rapid increase in blood glucose levels than others, which cause a gradual increase over time. Foods that are high GI are not necessarily unhealthy, although low GI foods often contain additional nutrients like fibre. It's more that low GI foods can help with appetite by making people feel fuller for longer, and this is something women with PCOS can struggle with.
Examples of low GI carbohydrates: Most fruits, green vegetables, beans, lentils, milk, brown rice, whole grain pasta and steel cut oats.
While both types of fibre (soluble and insoluble) are important for overall gut health, soluble fibre in particular has been shown to be helpful for those with PCOS, as fibre slows down digestion which means better glycaemic control. Soluble fibre can help to lower LDL (the ‘bad’ cholesterol) by binding with it and removing it from the body. This can also be helpful for women struggling with their weight and their PCOS.
Examples of high fibre foods: Cruciferous veggies (broccoli, cauliflower, cabbage and sprouts), peppers, squash, pumpkin, nuts, pulses, legumes and berries.
Timing of eating
The general advice to eat small portions regularly (every 3-4 hours) is often given for those with PCOS. This is so that insulin and blood sugar levels can be better regulated. You also feel satiated throughout the day and therefore less likely to overeat, which helps with weight management, too. Having said this, there is emerging evidence to suggest that time restricted eating patterns (within an 8-12 hour window in the day) may be beneficial for those with PCOS or insulin resistance. There are also studies demonstrating that avoiding late night snacking and avoiding eating within two hours from bedtime is linked to better blood sugar control and lower levels of obesity.
Omega-3 fatty acids can be found in vegetable oils and nuts, oily fish, flaxseed and leafy vegetables. In some studies, omega-3 fatty acids have been shown to be effective in reducing insulin resistance and reducing inflammation in the body. Alongside this, ensuring that your meals contain adequate amounts of healthy fats like these will likely also lower the overall glycaemic effect of the meal.
A word on weight
Having PCOS can increase the risk of becoming overweight, which can lead to other health complications such as diabetes, heart disease and sleep apnoea. If you have PCOS, healthy gradual weight loss can help to improve insulin sensitivity and help to regulate menstrual cycles. Healthy habits like eating nutritionally balanced meals, exercising for at least 30 minutes per day, ensuring you get enough sleep each night and managing your stress levels can really help with weight management. Sometimes, however, weight loss through lifestyle interventions proves to be challenging for those with PCOS, and there are now increasing numbers of studies indicating that for women with a BMI over 35 with comorbidities, support through specialist weight management services or even bariatric surgery could be an option for reducing symptoms.
Vitamin D deficiency is very common within the general UK population, and for women with PCOS, optimising levels of vitamin D has been shown to improve menstrual irregularities, promote fertility and improve insulin resistance. Very few foods contain vitamin D naturally, but some foods such as eggs, cereals, fish and mushrooms have been fortified with it to boost intake.
Omega-3 fatty acids
As previously mentioned, Omega-3 fatty acids can help to improve symptoms of PCOS. Many people within the UK either dislike fish or just don’t have very much of it in the UK. Therefore supplements are available at most pharmacies and health food shops.
Inositol has been shown in some women to improve insulin sensitivity, improve ovulation rates and regulate the menstrual cycle. There are a few different types of inositol, and some women may be resistant to some types. At this stage, despite some promising results, Inositol should only be treated as a supplement and has not got enough evidence base to recommend use and is not approved for use in the NHS. It is therefore only an experimental treatment sometimes used alongside other treatments recommended by registered healthcare professionals.
PCOS is slowly becoming more prevalent amongst women of reproductive age, and unfortunately given the obesity epidemic projection, it may become even more so. While research is still building up, raising awareness of the disorder could help to recognise symptoms much earlier and also encourage women to seek help.
If you are struggling with PCOS and your symptoms, please come forward and contact your GP. There are ways of reducing symptom discomfort and the disease impact should you want or require an intervention.
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