5 Benefits of N-Acetylcysteine (NAC) for PCOS

N-acetylcysteine, simply known as NAC, is a powerful antioxidant that can offer help to women who have polycystic ovary syndrome (PCOS). Known in Europe for decades as an immune boosting supplement and as a popular treatment for bronchitis, NAC is emerging as a promising integrative treatment for women who are having complications from PCOS. Here are five great benefits of NAC for women with the condition:

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Boosts Fertility

For the approximately 70 percent of women with PCOS who experience infertility, NAC may offer some hope. A systematic review and meta-analysis published in the Journal of Obstetrics and Gynecology looked at the benefits of NAC in eight randomized controlled trials involving 910 women with PCOS. The review showed that NAC provided significant improvements for improving ovulation, pregnancy and live birth rates as compared to a placebo alone.

NAC has been shown to have similar benefits as metformin for improving pregnancy rate, spontaneous ovulation, and improving menstrual regularity in women with PCOS.

For women who are resistant to Clomid, NAC may help to improve their fertility as well. In a study published in the European Journal of Obstetrics, Gynecology, and Reproductive Biology found that NAC users had a nine times higher ovulation rate and a five times higher pregnancy rate in Clomid resistant women than compared with a placebo.

Improves Insulin Resistance

NAC is emerging as a promising option for women with PCOS to improve their insulin levels. An important action of NAC is to protect insulin receptors and influence insulin receptor activity secretion from the pancreas cells. As a result, NAC can improve insulin resistance.

Although it’s not FDA approved for its use, metformin remains a commonly-prescribed medication to help women with PCOS who have insulin resistance. Several studies have compared NAC and metformin in women with PCOS. Women who took NAC showed similar results to metformin for improving insulin resistance as well as lowering cholesterol levels, and without experiencing the common gastrointestinal side effects that metformin can cause.

Restores Hormone Balance

A surprising benefit of NAC is that it has the potential to lower androgen levels and regulate menstrual cycles. In their study, Oner and colleagues randomized women with PCOS to take metformin (500 mg, three times daily) or NAC (600 mg three times daily) for 24 weeks. Both treatments resulted in significant decreases in hirsutism score, free testosterone, and menstrual irregularity.

Fights Inflammation

Women with PCOS have been shown to have higher levels of oxidative stress than women without PCOS. High levels of oxidative stress can damage cells and promote inflammation which in turn worsens the metabolic aspects of PCOS. As a powerful antioxidant, NAC works to fight oxidative stress and reduce inflammation.

Helps Your Liver

Sometimes women with PCOS develop non-alcoholic fatty liver disease. This type of fatty liver disease can result from high insulin and triglyceride levels and can be reversed with modifications in your diet.

NAC has been shown to help improve fatty liver in women with PCOS. A study published in Hepatitis Monthly showed that women with PCOS who were treated with NAC (1200 mg/daily) for three months showed a significant improvement in lowering liver function tests, markers of fatty liver.

Overall, NAC is a well-tolerated dietary supplement that offers numerous benefits to women with PCOS. If you’re interested in trying NAC to see if it will help you get pregnant or reduce some of the metabolic consequences of PCOS such as fatty liver and insulin resistance, talk with your healthcare provider and registered dietitian nutritionist to determine what dose is appropriate for you.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  8. Oner G, Muderris II. Clinical, endocrine and metabolic effects of metformin vs N-acetyl-cysteine in women with polycystic ovary syndrome. Eur J Obstet Gynecol Reprod Biol. 2011;159(1):127-3. doi:10.1016/j.ejogrb.2011.07.005

  9. Mohammadi M. Oxidative stress and polycystic ovary syndrome: a brief review. Int J Prev Med. 2019;10:86. doi:10.4103/ijpvm.IJPVM_576_17

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Additional Reading
  • Oner G et al. Clinical, endocrine and metabolic effects of metformin vs N-acetyl-cysteine in women with polycystic ovary syndrome. Euro J Obst Gynecol Biol. Nov 2011;159(1):127-131.

By Angela Grassi, MS, RDN, LDN
 Angela Grassi, MS, RDN, LDN, is the founder of the PCOS Nutrition Center.