What is PCOS?
PCOS is marked by lack of ovulation and missed or irregular menstrual periods. It affects up to 10% of women of reproductive age, making it the most common cause of female infertility. Genetics likely play a role--women with PCOS are more likely to have a mother or sister with the condition as well.
Women with PCOS have a hormonal imbalance: All women have some male hormones, but in PCOS, the ovaries produce more androgens than they should. Though thin women can have PCOS too, insulin resistance, a condition that can lead to high blood sugar levels and weight gain, is also related to PCOS.
Beyond the health issues--cardiovascular disease, excessive body hair growth, weight gain and obesity, thinning hair on the head (male pattern baldness), acne, dark skin patches, pelvic pain, dandruff, ovarian cysts, anxiety, depression, and sleep apnea, to name a few--is the anguish of wanting a child and failing to become pregnant.
Timing and meal size matters
Researchers randomly selected 60 normal-weight women (55 completed the study) with PCOS to follow a "breakfast diet" or a "dinner diet" for 90 days. The women on the breakfast diet were instructed to eat 980 calories (kcal) for breakfast, 640 calories for lunch, and 190 calories for dinner. The dinner diet consisted of 190 calories for breakfast, 640 calories for lunch, and 980 calories for dinner.
In this way, the breakfast group consumed 54% of calories in the morning, 35% for lunch, and 11% at dinner; this pattern was reversed for the dinner group. The researchers collected blood samples and diet records to assess adherence to the prescribed diet. Compared with the dinner group, the breakfast group experienced beneficial reductions of several health markers, including an increase in ovulation rates. They also experienced a 105% increase in sex-hormone-binding globulin (SHBG) levels, which is a good thing, because if excessively high amounts of sex hormones, including testosterone, are bound up by the SHBG protein, they aren't free to interact with cells and cause symptoms.
Time it right
This study was small but it was controlled. Most women followed their assigned diet closely, and most completed the entire study. It also agrees with previous research showing more effective weight loss and improved glucose and insulin levels for people who eat most of their calories early in the day.
If you have PCOS, consider eating more of your calories in the morning. Include plenty of lean protein, complex carbohydrates, and healthy fat in each meal and snack.
A sample breakfast might include oatmeal with walnuts and raisins, whole grain toast, plain Greek yogurt, and scrambled eggs cooked with olive oil. This sounds like a lot, but remember, you'll be eating less for lunch, and much less for dinner. Talk with your doctor, nurse, or dietitian to let them know you'd like to try this approach.
An old saying suggests that for optimal health, eat "breakfast like a king, lunch like a prince, and dinner like a pauper." This may just be the best diet advice for women with PCOS.
(Clin Sci 2013;125:423-32)