N-acetylcysteine (NAC) is a molecule few people have even heard of, but is incredibly valuable when it comes to natural health support. It is in fact an altered and more stable form of the amino acid cysteine. Cysteine itself is present in most high protein foods such as meat, fish and dairy products. Vegans get most of their cysteine from plant sources such as granola and oat flakes, as well as vegetables like broccoli, red pepper and onion.
As a supplement, the more stable NAC is both safe and inexpensive, and has been commercially available for a long time. It’s also generally well-tolerated.
Its importance stems from the fact that it is a precursor for endogenous glutathione biosynthesis. The body converts NAC to cysteine, which is then converted to glutathione. Glutathione is one of the body’s main antioxidants, helping to reduce free radical damage and playing a role in detoxification. Not surprisingly, NAC has been shown to support general health in many respects, ranging from heart to mental health issues. While its benefits have been explored for many realms of health, studies on its role in fertility in general and polycystic ovarian syndrome (PCOS), which is a major reason for female subfertility, specifically, are rather recent.
NAC and fertility
A number of studies have demonstrated the benefits of NAC supplementation for fertility in both men and women. In men, NAC has been shown to improve sperm quality in subfertile men. In women, research has revealed significant benefits for endometriosis patients and patients suffering from recurrent pregnancy loss.
NAC and PCOS
Interestingly, general research on NAC has revealed a role in insulin sensitivity. The terms insulin sensitivity and its opposite insulin resistance describe the way body cells respond to our blood sugar hormone insulin. Due to the fact that insulin not only regulates blood sugar levels, but also certain aspects of our endocrine system, scientists were soon wondering whether it might be an interesting natural treatment option for patients with PCOS as well.
NAC ameliorates metabolic and endocrine characteristics of women with polycystic ovary syndrome (PCOS)
Researchers did not have to wonder for long: In a randomized double-blind clinical trial on 94 women with diagnosis of PCOS without additional complications, oral treatment with NAC for 24 weeks resulted in significant improvements of metabolic parameters. Specifically, lipid profile and fasting blood sugar (FBS) as well as fasting blood insulin was much improved after treatment.
In a meta-analysis of 18 studies, including 2,185 participants, NAC significantly reduced total testosterone levels and increased FSH levels.
NAC improves ovulation
Frequent symptoms of polycystic ovarian syndrome include irregular or missing ovulations. Current medication to improve this are often accompanied by side effects and do not work for every woman.
Analysis of eight studies with a total of 910 women with PCOS showed that treatment of PCOS patients with NAC could significantly improve ovulation as compared to placebo. In addition to that, higher odds of having a live birth and getting pregnant in the first place were recorded.
NAC improves oocyte quality
These latter observations may find their explanation in the results of a rather recent study which found that NAC treatments of PCOS patients can improve egg quality. This is particularly important if you are going through IVF treatments or are trying to get pregnant when you are older than 35. In the study of women suffering from PCOS, the group who received a NAC supplement saw a decrease in the amount of abnormal ovarian cells and a significant increase in embryo quality .
NAC is widely available as an oral dietary supplement and is relatively inexpensive.
If you are currently taking an antidepressant or undergoing cancer treatment, be sure to discuss the use of NAC with your physician, as it may interact with some antidepressants and chemotherapy. Other than that, it is virtually free of side effects when taken in moderate dosages of no more than a few hundred mg daily.
In combination with other micronutrients important for PCOS patients, NAC is available as part of Fertilovit F PCOS. This is a formula designed to dietetically support women with PCOS who are planning for pregnancy.
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