Endometriosis is a common female hormonal disorder characterized by estrogen dominance and endometrial-like tissue growing à l'extérieur the uterus. (Recall that the endomètre is the lining of the uterus or womb.) Endometriosis is estimée to affect between 2-10% of women and at least 50% of women who struggle with infertility [1]. It is an inflammatoire condition that often manifests in debilitating pelvic pain, heavy periods, abnormal bleeding, and infertility [2]. On the other hand, endo can also be hidden, showing few or no symptoms, which can make it difficult to diagnose.
Currently, the “gold-standard” treatment for endometriosis is laparoscopic surgery to remove endometrial lesions. Unfortunately, this chirurgie can be expensive and does not guarantee that endometrial lesions won’t regrow in the future. Another common form of treatment is hormonal birth control, which suppresses symptoms but does not cure endometriosis. Additionally, this treatment can have harmful side effects.
Because of these less-than-ideal treatment methods, some researchers are seeking better treatment alternatives for endometriosis. One promising treatment for endo may be supplementation with N-acetylcysteine, known as NAC.
What is N-acetylcysteine?
NAC is a supplement form of the amino acid L-cysteine. It has an anti-inflammatoire and antioxidant effect on the body, making it an effective traitement for acetaminophen (Tylenol) overdose [1][3]. It also has the potential to treat cancer, lung disease, insulin resistance, blood clotting, and, as we are going to look at today, fertility diseases like endometriosis [3].
What did we already know about N-acetylcysteine’s effects on endometriosis?
A previous étude from 2013 observed women with confirmed ovarian endometrial lesions who were or were not treated with NAC over a 3-month period [2]. Those treated with NAC experienced a significant number of decreased or disappearing lesions. Fewer women in the NAC treatment group experienced enlarged or new cysts compared to untreated women. The NAC treatment group also reported lessened pelvic pain.
A newer study shed more light on whether NAC could help women with endometriosis
From January 2020 to April 2022, 120 women aged 18-45 years old who had been diagnosed with endometriosis and were being treated through the endometriosis outpatient service of Policlinico Umberto I-Sapienza University Hospital (in Rome, Italy), participated in une étude. The researchers’ goal was to further demonstrate the positive effects NAC supplementation has on endometriosis. They also wanted to evaluate whether NAC could positively affect fertility.
All of the patients were treated with 600 mg of oral NAC supplementation, 3 days a week for 3 months. The patients were assessed for endometriosis symptom severity before and after treatment. Their endometrial lesions were also measured through ultrasound before and after treatment. Researchers also assessed pregnancy rates in a subgroup of women who sought to conceive.
N-acetylcysteine supplementation reduced pain and endometrial lesion size
The Italian study concluded that oral NAC supplementation is a viable method of treating both endometriosis pain and the size of ovarian endometriomas. Throughout the treatment, the intensity of endometriosis symptoms, including painful periods, significantly improved. Ovarian endometriomas (endometrial lesions on the ovaries) present avant treatments demonstrated significant size reduction at the end of the three months.
Strikingly, 75% of the subgroup of women treated with NAC who desired to conceive (that is, 39 out of 52) achieved pregnancy without reproductive treatments within 6 months of beginning NAC supplementation.
Strikingly, 75% of the subgroup of women treated with NAC who desired to conceive (that is, 39 out of 52) achieved pregnancy without reproductive treatments within 6 months of beginning NAC supplementation.
An additional observation was a decrease in BMI for many of the participants.
N-acetylcysteine appears to be safe, affordable, and effective
The researchers also noted that no negative side effects were discovered, suggesting that NAC is a safe, affordable, and effective form of endometriosis treatment. Because the goal of this study was to confirm the findings of past research, the researchers noted the findings as conclusive. Still, studies with much larger sample sizes than 120 participants are necessary to truly confirm NAC’s benefits for women with endometriosis.
Should you supplement with NAC?
NAC supplements can be bought over the counter. As with any supplement, before you get started, discuss NAC supplementation with your doctor or other healthcare professional to ensure it does not interact with any of your current medications or health conditions. Also, you may first want to try increasing high-protein foods in your diet like beef, chicken, eggs, and whole grains. These foods are natural sources of cysteine, which NAC is the supplement for.
If your provider recommends NAC supplementation, the typical recommendation ranges are between 600 to 1,800 mg daily. It is worth noting that the participants of the 2023 study only took 600 mg three times a week, so NAC may not need to be a daily supplement for a woman to see benefits [1]. This is another reason to discuss N-acetylcysteine supplementation with your healthcare professional.
The bottom line on N-acetylcysteine for endometriosis
Certainly, N-acetylcysteine supplementation alone may be insufficient to adequately treat endometriosis. But given how safe, inexpensive, and easy to access it is, it may be a great place to start or something to try alongside other endometriosis treatments. And since infertility co-exists with endometriosis for many, many women, N-acetylcysteine’s potential benefits on fertility may be an added bonus.
