N-Acetyl Cysteine
NAC (N-acetyl cysteine) is an altered form of the amino acid cysteine, which is commonly found in food and synthesized by the body.
- Reliable and relatively consistent scientific data showing a substantial health benefit.
- Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
- For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.
Our proprietary “Star-Rating” system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by the medical community, and whether studies have found them to be effective for other people.
For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.
This supplement has been used in connection with the following health conditions:
| Used for | Amount | Why |
|---|---|---|
Bronchitis | 400 to 600 mg daily |  [3 stars] NAC, which appears to work by reducing the thickness of mucus, has been shown to be a safe and effective treatment for chronic bronchitis. |
Chronic Obstructive Pulmonary Disease | 200 mg three times daily | [3 stars] N-acetyl cysteine helps break down mucus and supplies antioxidant protection to lung tissue. |
Angina | 600 mg three times daily (under medical supervision if taking nitroglycerin) |  [2 stars] Under a doctor’s supervision, supplementing with NAC may improve the effects of nitroglycerin. |
Autism | Use with a doctor’s supervision | [2 stars] A double-blind study found that supplementing with NAC for 12 weeks improved symptoms of irritability in children with autism.
|
Gastritis | 1 gram daily | [2 stars] In one study, people with atrophic gastritis given NAC saw increased healing. |
Heart Attack | Consult a qualified healthcare practitioner | [2 stars] In one study, NAC injections decreased the amount of tissue damage in people who had suffered a heart attack. |
HIV and AIDS Support | 800 mg daily | [2 stars] Supplementing with NAC may slow the decline in immune function. |
Smoking Cessation | Refer to label instructions | [2 stars] N-Acetylcysteine (NAC) has been found to be beneficial in the treatment of various types of addiction, including tobacco addiction in one double-blind trial. |
Unverricht-Lundborg Disease | Requires a doctor's supervision | [2 stars] Several case reports suggest oral NAC may improve symptoms of Unverricht-Lundborg disease, an inherited degenerative disorder involving seizures and progressive disability. |
Bipolar Disorder | Refer to label instructions |  [1 star] In a preliminary trial, depression in patients with bipolar disorder significantly improved after NAC treatment.
|
Lupus | 600 mg three times per day | [1 star] In a case report, a woman with kidney disease due to SLE (lupus nephritis) may have had an improvement in her kidney function due to treatment with N-acetylcysteine (NAC).
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Neuropathy | 1,200 mg daily | [1 star] A small body of evidence suggests N-acetyl cysteine may help prevent neuropathy. |
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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.