China: A recent study has claimed that N-acetylcysteine (NAC) is effective in improving metabolic parameters in polycystic ovary syndrome (PCOS) and may be a promising nutritional supplement for PCOS treatment. Findings from the systematic review and meta-analysis were published in Frontiers in Nutrition on September 29, 2023.
Polycystic ovary syndrome is a common endocrine disorder in women of reproductive age. It is often accompanied by metabolic disorders. Metformin as an insulin sensitizer is widely used to improve the metabolic function of PCOS but may have gastrointestinal side effects. Emerging evidence indicates that N-acetylcysteine improves metabolic parameters in PCOS and may be a potential alternative to metformin.

No meta-analysis has reported the relationship between NAC supplements and metabolic parameters in PCOS women. Currently, the relationship between the two is mainly derived from RCTs, so it is imperative to summarize relevant studies to obtain quantitative data between NAC and PCOS women’s metabolism.
Jiajun Liu, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China, and colleagues, therefore, aimed to comprehensively review published population-based randomized controlled trials (RCTs) to evaluate the effect of NAC on metabolic parameters in patients with PCOS and to obtain preliminary quantitative data on this effect by meta-analysis.
For this purpose, the researchers searched four online databases from inception to April 1, 2023. The heterogeneity between studies was determined by employing the I2 statistic and Cochrane’s Q test, with an I2 value >50% considered significant. The data was expressed as standardized mean differences. The final analysis included a total of 11 RCTs comprising 869 women with PCOS.
The researchers reported the following findings:

NAC caused more changes in body weight (SMD: −0.25), body mass index (SMD: −0.16), ratio of fasting blood glucose to fasting insulin (SMD: 0.38), fasting insulin (SMD: −0.24), total cholesterol (SMD: −0.11), triglycerides (SMD: −0.18), and low-density lipoprotein (SMD: −0.09) compared with metformin.
Compared with metformin or placebo, NAC significantly reduced fasting blood glucose levels (SMD: −0.23; SMD: −0.54, respectively).
NAC significantly reduced total cholesterol (SMD: −0.74), and this effect was observed when NAC was compared with placebo.
NAC reduced HDL levels in women with PCOS compared with metformin (SMD: −0.14).
The study on PCOS treatment provides additional evidence that NAC may be a potential therapeutic intervention for PCOS.
The researchers wrote, "Like metformin, NAC is well-tolerated and can improve metabolic disorders in women with PCOS, which may be more conducive to long-term PCOS management."
Reference:
Liu, J., Su, H., Jin, X., Wang, L., & Huang, J. (2023). The effects of N-acetylcysteine supplement on metabolic parameters in women with polycystic ovary syndrome: A systematic review and meta-analysis. Frontiers in Nutrition, 10, 1209614. https://doi.org/10.3389/fnut.2023.1209614