Guest post by Dr. Shawna Darou, ND
N-acetyl cysteine (NAC), is a common PCOS supplement and is a form of the essential amino acid cysteine, which is used to make glutathione, the body’s main antioxidant. By raising glutathione levels, your cells are protected from reactive oxygen species, and protected against DNA damage and cancer development. The other main mechanism for NAC is in modulating inflammation both acutely from viruses, and also in chronic inflammatory conditions.
A review of studies with NAC show the following incredible and diverse health benefits for various conditions:
- Replenishing intracellular glutathione levels, which can become deficient with age and chronic illness.
- Protection against flu symptoms, meaning it reduces the severity and likelihood of having flu symptoms when exposed to the flu virus (1).
- Reduction of the frequency and duration of attacks in chronic obstructive pulmonary disease (COPD) and slowing the profession of pulmonary fibrosis.
- Blocks cancer development due to the reduction in oxidative stress and inflammation. NAC also induces cell death in multiple types of human cancer cells, slows tumor growth, protects the lungs from cigarette smoke-induced cancer, and shrinks colon polyps. In these and other mechanisms, NAC is considered a supplement for cancer chemoprevention (2,3,4,5,6).
- Inhibits growth of Helicobacter pylori infection in the stomach and reduces the production of inflammatory cytokines produced by this organism which can lead to gastritis and cancer (7,8).
- Reduction of symptom in obsessive-compulsive syndrome with daily use, including compulsive hair pulling, nail biting, skin picking, and even compulsive gambling (9,10).
Specifically for PCOS, NAC has an impact on insulin resistance, ovulation response and hormone balance. It is certainly a supplement worth considering, in addition to work with your nutrition, exercise and stress management plan.
6 Ways NAC supports your PCOS:
Improves insulin sensitivity
Several studies have looked at the role of NAC in women with insulin resistance, and even compared with metformin. A reasonable dosage of 600 mg of NAC daily worked equally well to metformin, where both treatments resulted in lower fasting insulin, a significant decrease in weight, lower free testosterone and hirsutism and improved menstrual regularity. As you read more health benefits of NAC, you will understand why this supplement is likely a superior choice to metformin due to the other positive impacts (11, 12)
Lowers testosterone levels and free androgen index
Due to the effect on overall hormone balance, studies also show a significant drop in testosterone levels and also what is called the free androgen index which measures the ratio of testosterone to SHBG (sex hormone binding globulin) as an indicator of how much free testosterone is circulating (11,12). NAC offers an additional support to lower some of the more annoying symptoms of PCOS related to high androgens such as acne, hair loss and hirsutism.
Improves menstrual regularity and frequency of ovulation
NAC alone can improve menstrual and ovulation regularity as in the study comparing it to metformin above. Another study combined NAC with l-arginine supplements showing many cases of restored ovulatory cycles. Women with PCOS tend to have higher free radical levels which lowers nitric oxide. Nitric oxide has a positive role in the egg maturation process and ovulation (11, 13).
Supports egg quality for fertility
Through increasing intracellular glutathione levels, NAC can protect egg quality. In an additional study looking at egg quality for IVF cycles, and again in comparison to metformin, women treated with NAC for 6 weeks prior to their fertility treatment showed significantly better egg and embryo quality (14), and hence had higher fertility rates. This is worth considering, especially if you are trying to conceive over age 35 and need additional egg quality support.
Lowers total cholesterol and LDL levels
An added bonus to reducing insulin resistance and weight loss is a positive change in lipid levels. In women with PCOS, there was also noted a decrease in both total cholesterol and low-density lipoprotein levels (11).
Works together with Clomid for improved fertility, better ovulation rate and higher progesterone levels
When Clomid (clomiphene citrate) is combined with NAC for fertility, there is a significantly improved ovulation rate, compared to Clomid alone, along with better endometrial thickness and progesterone levels (15). It is important to note that a very common side-effect of Clomid treatment is a thin endometrial lining, which is corrected by the addition of NAC. NAC will also boost ovulation rates in women who are ‘Clomid-resistant’, meaning that Clomid on its own will not induce ovulation. When combined with NAC, ovulation rates in one study went up from 1% to 49%, which is a very significant change (16).
Dosage and safety:
The therapeutic dosage of NAC in almost all of the published studies is 600 mg 3x daily. If you are significantly overweight, a higher dose, closer to 1000 mg 3x daily may be required to see the benefits.
NAC is considered a very safe supplement. The most common side-effect is stomach upset, usually being acid reflux of gastric irritation. This is usually resolved by taking the supplement with food rather than on an empty stomach, and not combining with coffee. There is some caution in people with asthma.
Dr. Shawna Darou is a licensed and registered Naturopathic Doctor, who graduated from the Canadian College of Naturopathic Medicine (www.ccnm.edu) at the top of her class and was the recipient of the prestigious Governor’s Medal of Excellence. Naturopathic medicine is her second career, her first being Engineering Chemistry from Queen’s University. She now uses her analytical brain and problem solving skills especially in the complicated arena of hormonal health, and in solving health puzzles.
Dr. Shawna Darou N.D. is a specialist in women’s health care and fertility who has treated thousands of women in her Toronto clinic since 2004. She is a dedicated and caring doctor with a gentle approach who is committed to the health of her patients. Dr. Darou’s is also an avid health writer, and her popular health blog can be found at http://darouwellness.com/blog-posts/
Outside of the office, Dr. Darou is the mother of two beautiful children who inspire her to evolve the medical model in order to reform healthcare for the next generation.
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