N-acetyl-cysteine (NAC) has emerged as a promising supplement for supporting both optimal detoxification and hormone balance. The liver plays an important role in hormone function and metabolism through its support of detoxification and antioxidant systems. Even slight fluctuations in hormone levels can trigger a cascade of responses throughout the body, emphasizing the critical role of hormone balance in maintaining optimal health. Several studies have investigated the effectiveness of NAC in the reproductive performance of females. However, the elimination of publication bias using trim and fill analysis revealed that NAC also could decrease E2 levels and endometrial thickness. Sensitivity analysis revealed that the overall effect size did not depend on one individual study. Subgroup analysis was not performed due to the low number of studies. The functional foods which include the fiber-containing foods such as inulin, have the ability to improve health and wellbeing . The beneficial effects of prebiotics were also found to improve metabolic disturbance in obese animals by altering the composition and metabolism of gut microbiota . Furthermore, testosterone replacement could improve performance in a verbal memory test and spatial learning and memory in healthy hypogonadal men or men with Alzheimer’s disease . Male rodents with an orchiectomy demonstrated dendritic spine loss , which could be restored by testosterone or Dihydrotestosterone (DHT) replacement 4,5. Here we report that metabolic disturbance was not observed in the ORX rats, but gut dysbiosis was found in these rats. However, no significant effect was observed on the number of follicles, endometrial thickness, progesterone, serum luteinising hormone levels and sex hormone-binding globulin. Eighteen studies, including 2185 participants, were included in the present meta-analysis. Polycystic ovary syndrome (PCOS) is one of the most common endocrine diseases characterised by unusual levels of sex hormones and dysfunction of the ovaries. "NAC is a precursor to the amino acid L-cysteine, which helps the body synthesize glutathione, arguably the most important antioxidant and support for detoxification in the body," he explains. By raising glutathione, NAC strengthens your antioxidant defenses, reduces oxidative stress, and supports detox pathways. NAC (N-acetylcysteine), on the other hand, is an amino acid derivative that helps your body make glutathione—your strongest internal antioxidant and detoxifier. Regular physical activity contributes to the regulation of various hormones and can help to reduce inflammation and oxidative stress, promoting optimal endocrine function. It must be noted that the GSH levels might be effective in the relationship between NAC and reproductive biomarkers(Reference Atkuri, Mantovani and Herzenberg50). Therefore, NAC, through decreasing lipid peroxidation, could have beneficial effects on reproductive biomarkers. Participants of included studies in seventeen of eighteen studies had PCOS. Regarding TT, studies with shorter duration had smaller sample sizes than studies with longer duration studies. In other investigated variables, extending supplementation duration was ineffective in the overall results. A comparison of two meta-analyses with the subjects of NAC and l-carnitine supplementation on inflammatory and oxidative stress biomarkers revealed that NAC had better effects than l-carnitine(Reference Faghfouri, Zarezadeh and Tavakoli-Rouzbehani6,Reference Fathizadeh, Milajerdi and Reiner44) . Other mechanisms proposed for the effects of l-carnitine on FSH and LH levels could be attributed to the regulation of lipid peroxidation and activity of antioxidant enzymes(Reference Rezaei, Mardanshahi and Shafaroudi43). Therefore, a definite interpretation of more decreasing effects of NAC on E2 levels than metformin needs more studies. Another study revealed that alcohol consumption is related to change in plasma sex hormone levels in premenopausal women(Reference Sarkola, Mäkisalo and Fukunaga38). Naimi et al. reported that NAC alone had no significant beneficial effect on the number of ovarian follicles and the levels of hormones in adult rats. Sensitivity analysis demonstrated that the overall effect size regarding the effects of NAC on LH did not depend on one individual study. Subgroup analyses for the effects of N-acetylcysteine on ovulation and sex hormones profile (95 % confidence intervals) The results of evaluating the quality of the included studies are presented in online Supplementary Fig. The duration of the intervention varied from 5 d to 24 weeks among the studies. Overall, eighteen clinical trials published between 2002 and 2021 were included in the meta-analysis. Overall, eighteen articles met the inclusion criteria and enrolled in the meta-analysis. Hormones are also metabolized and eliminated through these systems, emphasizing the important role of the liver in maintaining optimal hormone balance (19). Antioxidant defenses work in tandem with these pathways, neutralizing ROS, safeguarding the liver from oxidative stress, and maintaining overall cellular health. This delicate equilibrium is influenced by hormone production, transport, and metabolism. This study was approved by the ethics committee of the Azad Medical University. RJ, MN, KP and NH contributed in conception, design, statistical analysis and drafting the manuscript. The primary data for this study is available from the authors upon direct request.