One scientifically proven benefit of NAC:

Treatment of acetaminophen overdose. By boosting levels of glutathione, NAC speeds up the breakdown of acetaminophen. You may be able to prevent liver or kidney damage if you get treatment within 8-10 hours of acetaminophen poisoning.

Go to the hospital if you or a loved one takes too much acetaminophen. A health professional may need to give you a high dose of the supplement through a vein in your arm.

Additional benefits of NAC

Treatment of chronic lung diseases. NAC supplements, particularly the kind you breathe in, may lessen inflammation in your airways. This might reduce the number of future flare-ups caused by COPD and improve lung function, but not all studies have found these results.

The supplement may also help to decrease the severity of wheezing and coughing in some people with ongoing bronchitis. More studies are needed to confirm these results.

High-dose NAC (1,200 milligrams per day) may also help lower inflammation, break up biofilms where germs live, and lessen damage caused by oxidative stress in the lungs and airways of people with cystic fibrosis, when used alone or with other medications.

Improve liver and kidney function. Your liver and kidneys flush drugs and other toxins out of your body. NAC supplements can speed up this breakdown process and may help your organs work better if you have liver or kidney disease. But more research is needed to know for sure.

Viral suppression. There aren’t many studies on NAC and the immune system, but current research suggests that it and glutathione may help to improve immune function in people with HIV. Some research shows that the supplement may help to suppress HIV-1 reproduction. But more research is needed to know if NAC has a big benefit for people with HIV/AIDS.

Test tube studies also show that NAC may stop the flu virus from replicating. In one 6-month study, people who took 600 milligrams of NAC twice a day reported fewer flu symptoms than people who didn’t take the supplement.

Balance blood sugar in people with insulin resistance. Research suggests the NAC may help to improve insulin resistance – when your body doesn’t respond to insulin, the hormone that keeps your blood sugar in check.

There’s some evidence the supplement may be particularly helpful for people with insulin resistance who have polycystic ovary syndrome (PCOS), a hormonal condition that interferes with periods and the ovaries.

Researchers have found little evidence that NAC can help people with type 2 diabetes gain good control over their blood sugar or increase their sensitivity to insulin.

Boosts brain function. NAC helps to refill glutathione levels in the body. It also aids in controlling a neurotransmitter called glutamate and can lessen inflammation and damage caused by oxidative stress. These functions may help protect cells needed for brain health, which may benefit people with neurodegenerative conditions such as Alzheimer’s and Parkinson’s diseases.

Improves treatment for mental health conditions. Researchers have found mixed results when it comes to how well NAC works to treat psychiatric disorders, but there’s promising evidence that the supplement may change the brain and nervous system in a way that helps lessen symptoms associated with:

• Major depressive disorder
• Schizophrenia
• Bipolar disorder
• Posttraumatic stress disorder (PTSD)
• Obsessive-compulsive disorder
• Trichotillomania (hair pulling)
• Substance use disorders

Some studies show that the supplement may help ease symptoms of withdrawal, including a strong urge or craving to take drugs. This may lessen the chances of relapse in people who’ve stopped misusing substances such as stimulants, cannabis, tobacco, and alcohol.

N-acetylcysteine for skin picking. NAC may improve symptoms of excoriation disorder, also called skin-picking disorder (SPD). One study found that people with SPD who took 1,200-1,300 milligrams of NAC daily for 3 months reported fewer SPD behaviors than those who didn’t take the supplement.

Lowers heart disease risk. Studies on human cells show that, when combined with green tea, NAC may help lessen damage caused by LDL cholesterol. LDL is the “bad” kind of cholesterol associated with heart disease.

Helps with fertility. NAC may improve fertility in people of all sexes. One study found that men who had trouble with infertility improved their semen quality when they took NAC alone or with selenium.

NAC may also help women ovulate regularly, particularly if you have infertility associated with a condition like PCOS.

Other uses of N-acetylcysteine

More research is needed, but there’s a small amount of evidence that NAC may:

• Prevent cell damage that may turn into cancer
• Lessen side effects from cancer treatment
• Control inflammation and reduce asthma attacks
• Dissolve blood clots
• Ease symptoms of Sjögren syndrome, an autoimmune condition that causes dryness
• Be useful in treatment of inflammatory conditions like lupus or rheumatoid arthritis.

Researchers continue to study the benefits of NAC on cancer and its treatment, including triple-negative breast cancer, colon cancer, liver cancer, and lung cancer in smokers. But there isn’t strong enough evidence to say that the supplement can prevent cancer.