N-Acetylcysteine
NAC is a precursor to L-cysteine and glutathione (master antioxidant). PROVEN life-saving for acetaminophen overdose. B-grade evidence for respiratory conditions (bronchitis, COPD) and blood glucose in PCOS. Widely studied for psychiatric conditions (OCD, addiction, depression) but evidence is mixed. Acts as mucolytic, antioxidant, and glutathione precursor. FDA controversially questioned its supplement status in 2020 but enforcement relaxed. Generally safe but may have pro-oxidant effects at very high doses. One of the most researched nutraceuticals.
Quick Answer
What it is
NAC is a precursor to L-cysteine and glutathione (master antioxidant). PROVEN life-saving for acetaminophen overdose.
Key findings
- Grade B: Blood glucose (Polycystic Ovary Syndrome (PCOS))
- Grade B: Bronchitis Symptoms (Chronic Obstructive Pulmonary Disease (COPD))
- Grade B: Autism Symptoms (Autism Spectrum Disorder (ASD))
Safety
No specific caution or interaction language was detected in the current summary/outcome notes.
ℹ️ Quick Facts: N-Acetylcysteine
Quick Facts: N-Acetylcysteine
- Best Evidence:Grade B
- Conditions Studied:27
- Research Outcomes:72
- Grade B Findings:5
- Key Effect:Chronic Obstructive Pulmonary Disease (COPD)
Detailed Outcomes
Evidence by Condition
Best grade per condition (each condition may have multiple outcomes)
Research Citations (34)
Related Supplements
Curcumin
15 shared conditions · 502 outcomes
Curcumin is the primary bioactive substance in turmeric. It has anti-inflammatory properties and can alleviate symptoms of depression as well as improve pain and function in people with osteoarthritis.
L-Carnitine
14 shared conditions · 558 outcomes
L-carnitine can relieve leg pain in people with peripheral artery disease (PAD) and treat some aspects of metabolic syndrome. Although it’s often also used for fat loss, its effectiveness for that is questionable.
Vitamin D
12 shared conditions · 308 outcomes
Vitamin D is a fat-soluble vitamin that our skin synthesizes when exposed to the sun. It benefits us in many ways, from bone health to mood.
Resveratrol
11 shared conditions · 318 outcomes
Resveratrol is a bioactive molecule found in plant sources such as grapes, peanuts, blueberries, and, famously, red wine. Resveratrol has anti-inflammatory and antioxidant properties that benefit cardiovascular function, glycemic control, and lipid metabolism. Although it’s promoted for lifespan extension, there’s no evidence for this in humans and limited evidence in animals.
Fish Oil
11 shared conditions · 448 outcomes
Fish oil is a mix of mostly EPA and DHA derived from fatty fish. It reduces triglycerides, but does not seem to affect the rate of cardiovascular events. It appears to reduce the symptoms of depression and improve some painful, inflammatory conditions.
Chromium
11 shared conditions · 300 outcomes
Chromium is a mineral that occurs naturally in the earth’s crust and is found in small amounts in a variety of foods. Chromium supplementation seems to enhance the effects of insulin in the body, leading to improvements in insulin sensitivity and blood sugar regulation in people with insulin resistance. Although chromium has historically been considered an essential nutrient for the human body, current evidence challenges this notion.
Saffron
10 shared conditions · 390 outcomes
Saffron is a spice with antioxidant properties derived from the flowering plant Crocus sativus. When used as a supplement, saffron seems to be effective at reducing symptoms of depression and possibly anxiety.
Creatine
10 shared conditions · 433 outcomes
Creatine is among the most well-studied and effective supplements for improving exercise performance. It does this mainly by increasing energy availability during high-intensity activity. Creatine may also provide cognitive and mental health benefits in some contexts.