Can low-carbohydrate diet help reverse Polycystic Ovary Syndrome (PCOS)?
Polycystic Ovary Syndrome (PCOS) is a condition that has a strong impact on a woman’s fertility, and affects between 5% to 10% of women of child bearing age. Because a woman’s body doesn’t produce enough eggs when she suffers from PCOS, it can cause infertility and contribute to difficulties in falling pregnant.
Most cases of PCOS are not genetic, but they are all related to hormonal abnormalities. The reason not enough eggs are produced is because of an excess of the androgen, or ‘male’ hormones. Both men and women have androgen hormones, but men have them in much greater quantities. This hormonal imbalance means that the cysts that are a normal part of producing eggs, do not grow. So a woman with PCOS has a lot of small cysts on her ovaries that do not mature to release their eggs. Normally, once this process happened, the cysts would go.
Another consequence of the higher levels of androgen hormones is the increased risk of obesity, heart disease, diabetes, as well as a likelihood of having more facial hair.
Interestingly, a low-carb diet may help overweight women with PCOS. A recent study of 11 non diabetic, overweight women with PCOS who had an average age of 33 was conducted. The study compared a ‘standard’ diet with 56% carbohydrates and 16% protein, with a lower carb diet of 43% carbohydrate and 15% protein. The fat component of the lower carb diet was a lot higher than the standard diet, by 14%. The fat content of the low carb diet was almost evenly split between polyunsaturated fatty acids and monounsaturated fatty acids. The fat content of the standard diet was almost evenly split between the two types of fatty acids, but was slightly higher (by 3%) in the monounsaturated variety.
A third diet, one high in both carbohydrates and monounsaturated fatty acids, was also compared. The study participants only followed each diet for 16 days. They had a 3 week break between each diet, and tried all 3.
Because production of the androgen hormones are influenced by the presence of insulin, the researchers were interested in finding out whether a low carb diet could reduce the amount of insulin circulating in the body. They believed this would have an indirectly positive effect on PCOS.
The results of this study found that while hormones that were circulating weren’t significantly affected by the lower carb diet, the women’s cholesterol, fasting insulin levels, free fatty acids, and their response to insulin were positively affected. The fact that their response to insulin improved is an indicator of the possible benefit of a low carb diet to PCOS sufferers. And because the women only followed the diet for 16 days, this may be why their levels of circulating insulin were not more prominently affected.
In a recent 2020 study, 14 women with PCOS followed a ketogenic Mediterranean diet for 12 weeks. By the end of the study, they achieved lower blood glucose and insulin levels, improvements in reproductive hormone levels and function, reduction of heart disease risk factors, and an average weight loss of 20 pounds (9.4 kg).
The authors of the study state that: “Because elevated insulin is thought to contribute to the endocrine abnormalities in PCOS, a reduction in insulin would be expected to ultimately result in an improved endocrine profile.”
They go on to say that these improvements indicate that using a low carb type diet, with a lower calorie intake, would probably benefit overweight women who suffer from PCOS. Cutting back on carbs can lower insulin levels and reverse insulin resistance, which may help to balance the hormonal system. This can enable ovulation and a normal menstrual cycle, in addition to improving or eliminating other symptoms.
References:
- Mavropoulos, John C et al. “The effects of a low-carbohydrate, ketogenic diet on the polycystic ovary syndrome: a pilot study.” Nutrition & metabolism vol. 2 35. 16 Dec. 2005, doi:10.1186/1743-7075-2-35
2. Journal of Translational Medicine 2020: Effects of a ketogenic diet in overweight women with polycystic ovary syndrome