Dietary guidelines in PCOS, an update
I wrote my Managing PCOS for Dummies (Wiley) a few years ago and now and then I look at the latest research papers to see if anything else been published on the subject. A few new studies have emerged and evidence is mounting for established guidelines as still being relevant.
So, to summarise the dietary guidelines in PCOS, here are the main factors to consider.
1. Aim for a healthy weight for height
2. Follow a Mediterranean-style diet to lower inflammation
3. Eat carbohydrates with a Low Glycemic index (GI)
4. Avoid fast foods to lower intake advanced glycated end products (AGEs)
5. Eat a diet low in saturated fats
I am going to briefly expand on each point above.
1. Aim for a healthy weight for height
PCOS has no cure as such, but keeping weight within a normal range can help reduce symptoms. Many find they disappear if they keep themselves lean, especially if they exercise too. This is because the levels of insulin will be lower at a lower weight.
However, women with PCOS find it harder to lose weight and often feel very hungry. Regular meals and some snacks, while keeping control of calories is important. You could try portioning out your calories for the day so that breakfast is 20% of daily calories, lunch and dinner are 30% and then have two 10% calorie snacks.
So if you are following a 1300 kcal diet, for example, you would have 260 calories for breakfast, 390 for lunch and dinner each and two snacks at 130 calories each.
2. Follow a Mediterranean-style diet
PCOS is an inflammatory condition, which means the body produces substances that can attack certain tissues and organs and hence lead to illnesses such as heart disease and cancer.
The Mediterranean diet is known for being anti-inflammatory, high in vegetables, fruits, legumes, nuts, beans, cereals, grains, fish, and unsaturated fats such as olive oil. It usually includes a low intake of meat and dairy foods (and even a little red wine!).
3. Eat starchy foods with a Low Glycemic index (GI)
Although seemingly not so popular now, low GI foods are still worth pursuing in order to reduce levels of circulating insulin. When carbohydrate foods (foods containing sugars and starches) are broken down they release glucose into the bloodstream and some carbs release their glucose quickly and some more slowly.
A lot of glucose suddenly entering the bloodstream will trigger the release of insulin and a high circulating insulin level is the trigger for many PCOS symptoms. In PCOS the level of insulin circulating can get quite high (more is released than someone without PCOS due to insulin resistance). So, slowing down the speed and amount of glucose entering the bloodstream is helpful. Aim to swap the high GI foods you eat for the lower ones listed below:
Low Glycaemic Index (GI=55 or less) | Medium Glycaemic Index (GI=56–69) | High Glycaemic Index (GI=70 and above) |
---|---|---|
Sweet potatoes | New potatoes | Potatoes (baked, mashed, chipped) |
Museli, porridge, All-Bran, Sultana-Bran | Basmati rice | Rice (white and brown) |
Breads - rye, granary, wholegrain, sourdough, fruit bread | Weetabix, Shredded Wheat | Corn Flakes, Rice Crispies, Cheerios, Puffed Wheat |
Fruit, vegetables, fruit juice, dried fruit, baked beans | Pitta bread, scone, wholegrain crispbread | White bread, French bread, crispbread, crumpets, wholemeal/brown bread |
Milk, soya milk, fromage frais, yoghurt, custard | ||
Pasta |
4. Avoid fast-foods
A high fast-food diet can overload you with chemicals called Advanced Glycation End-Products (AGEs). In general, fried foods and highly processed products contain high levels of these AGEs as they are formed during the cooking and processing process.
AGEs can increase inflammation in PCOS and disrupt levels of insulin and testosterone. Studies have shown that lowering intake of fast-food can improve many of the parameters that trigger symptoms in PCOS including testosterone and insulin levels.
5. Eat a diet low in saturated fats
Reduce the amount of saturated fat you eat by limiting your intake of the following foods:
- butter, ghee, suet, lard, coconut oil and palm oil
- cakes and biscuits
- fatty cuts of meat
- sausages and bacon
- cured meats (salami, chorizo and pancetta)
- cheese
Dietary saturated fatty acids (SFAs) can increase inflammation in PCOS and further increase insulin resistance.
Following the guidance above is also recommended for anyone with type 2 diabetes or prediabetes and unfortunately, the risk for type 2 diabetes is raised with PCOS.