It was observed that supplementation with NAC led to significantly greater changes when compared with metformin across an array of metabolic measures, including BMI, fasting insulin, ratio of fasting blood glucose to insulin, and total cholesterol levels.
Furthermore, when compared with metformin or a placebo, NAC was found to significantly reduce fasting blood glucose and total cholesterol levels.
The Chinese researchers concluded: “This study on the treatment of PCOS provides additional evidence that NAC may be a potential therapeutic intervention for PCOS. Like metformin, NAC can improve metabolic disorders in women with PCOS and is well tolerated, which may be more conducive to the long-term management of PCOS.”
PCOS is the most common endocrine disorder in women of reproductive age, which is known to affect around 6-13% of women. With symptoms including menstrual irregularities, fertility issues, hirsity, and mood disorders, the condition can have a significant impact to quality of life.
Furthermore, affected individuals can have a significantly increased risk of developing cardiovascular disorders (CVD), type 2 diabetes, and metabolic syndrome due to the occurrence of obesity and insulin resistance as additional PCOS features.
Due to a lack of an effective cure for PCOS, here has been a significant interest in identifying natural and effective nutritional therapies to alleviate symptoms. One such nutritional supplement includes N- acetylcysteine (NAC), which is the acetylated form of the L-cysteine amino acid, with studies highlighting its potential to regulate hormones and ovulation in women with PCOS.
Due to a lack of meta-analyses reviewing the influence of NAC on metabolic parameters, the present review sought to collate the evidence from RCTs investigating this evidence in women with PCOS.
The researchers collated 11 RCTs following a comprehensive search of databases including PubMed, Embase, Web of Science, and Cochrane Library. The studies included a total of 869 women with PCOS, which were analysed using I2 statistic and Cochrane’s Q test to determine between-study heterogeneity.
It was reported that NAC caused significantly more changes in BMI, bodyweight, fasting insulin, ratio of fasting blood glucose to insulin, total cholesterol, triglycerides, and low-density lipoprotein, when compared to metformin.
In addition, NAC was found to significantly reduce fasting blood glucose and total cholesterol levels when compared to metformin or the placebo.
The findings provide evidence that NAC may be effective in improving metabolic parameters in women suffering with PCOS, and show that NAC may have potential as a nutritional supplement for symptom management.
Regarding the proposed mechanisms of action of NAC on the metabolic outcomes, the researchers hypothesise: “According to published studies, oxidative stress may contribute to the pathophysiology of PCOS, and elevated levels of oxidative stress are linked to hyperinsulinemia and dyslipidaemia.
“Therefore, antioxidants may be beneficial in improving metabolic disorders in women with PCOS, which was demonstrated in another study. NAC can improve metabolic parameters in women with PCOS, which may be related to its antioxidant effect,” they add.
They emphasise that further large-scale RCTs are required to assess the effect on the differing phenotypes of PCOS.
Source: Frontiers in Nutrition
“The effects of N-acetylcysteine supplement on metabolic parameters in women with polycystic ovary syndrome: a systematic review and meta-analysis”
Jiajun Liu, Haodong Su, Xueshan Jin, Lan Wang, Jieming Huang.