By Dr. Andreas Eenfeldt, MD
medical review by Dr. Bret Scher, MD
Updated October 25, 2019
Polycystic ovary syndrome (PCOS) is common, affecting up to 10% of women of childbearing age. Beyond menstrual problems and other physical symptoms, it’s a leading cause of infertility.1
Fortunately, there’s a potentially effective lifestyle treatment available.
Symptoms
Here are the most common symptoms of PCOS:
- Menstrual irregularities like irregular, skipped or heavy periods.
- Inability to get pregnant.
- Acne
- Excess facial and body hair, showing up in a male pattern (including the upper lip, chin and chest).2
- Obesity
Cause and treatment
PCOS is much more common in women with excess weight, type 2 diabetes, previous gestational diabetes and other results of insulin resistance and excess insulin. This also includes hypertension and cholesterol abnormalities.3 Many believe that PCOS is caused directly by insulin resistance and high insulin levels, like the other problems listed above.
It is well known that lifestyle changes resulting in weight loss can improve PCOS symptoms, and so can the type 2 diabetes drug Metformin.4
Given the strong connection to excess weight, high insulin levels and other metabolic problems, a low-carb diet is potentially ideal for reversing PCOS. The low-carb diet is one of the most effective treatments that consistently and reliably lowers insulin levels and reverses the metabolic issues that include PCOS. Therefore, a low-carb diet should be considered for any treatment plan for PCOS.
Although not all studies agree, much of the limited available science shows great promise:
One small 2005 study followed 11 women with PCOS as they went on a ketogenic low-carb diet for six months. The 5 women who completed the study greatly improved their weight, hormonal status and perceived amount of body hair. Two of them became pregnant despite previous infertility problems.5
A 2013 study shows that even a very modest reduction in carbohydrates (from 55 to 41 percent of energy) can result in significant improvements in weight, hormones and risk factors for women with PCOS.6
Finally, a 2017 review of relevant studies finds that low-carbohydrate diets tend to “reduce circulating insulin levels, improve hormonal imbalance and resume ovulation to improve pregnancy rates”.7
Beyond the scientific evidence cited above, the clinical experience of doctors using it strongly support low carb as an effective treatment for PCOS.
Reversing PCOS and getting pregnant
There are lots of stories of women reversing their PCOS symptoms and even suddenly getting pregnant after going low carb. It can sometimes feel like a miracle. Although of course, it’s not that kind of miracle, so getting pregnant still requires a partner, even on low carb.
This is simply biology. Low carb can lower insulin and reverse insulin resistance in PCOS, helping to balance the hormonal system. This can enable ovulation and a normal menstrual cycle, while reducing or eliminating other symptoms.
Here are some brave women who have shared their stories:
https://www.dietdoctor.com/keto-intermittent-fasting-completely-blown-away-changes
https://www.dietdoctor.com/i-got-my-life-back
https://www.dietdoctor.com/how-bethany-reversed-her-pcos
https://www.dietdoctor.com/from-depression-meds-and-diet-pills-to-fasting-and-low-carb-eating
Professional experience
Many health care professionals have also found carbohydrate restriction incredibly effective for helping people with PCOS reverse their disease and get pregnant. This includes Australian dietitians.
The fertility specialist Dr. Michael Fox has more than a decade of experience helping patients with PCOS and infertility, using a low-carb diet.
Dr. Fox found that compared to only using drugs, adding a low-carb diet for PCOS patients increased the chance of pregnancy from 45 to over 90 percent! This saves many people from needing in vitro fertilization, a very expensive option that still sometimes fails, instead getting pregnant in a safe and inexpensive way.
Here are two interviews with Dr. Fox:
In the first one he discusses the benefits of low-carb diets (ideally below 20 grams of carbs per day) in PCOS.
https://www.dietdoctor.com/eat-get-pregnant
The second one is about how avoiding stressors – like frequent and intense exercise – can make it easier to get pregnant.
https://www.dietdoctor.com/women-hormones-and-nutrition-new-member-presentation
