# N-acetylcysteine (NAC) supplement

17 Hacker News commenters recommended N-acetylcysteine (NAC) supplement and 5 criticized it, November 2025 to November 2026. It was recommended in 5 of 13 months. It meets the Hacker Approved badge rule.

**Verdict:** People recommend NAC as a cheap, generally safe supplement that they say helps with hangovers, brain fog, and stress, and that is widely studied. Critics say long-term safety data is limited and that it can worsen liver damage if taken after drinking.

## Why people recommend it

- Generally safe, low risk (2 comments): "It seems to be safe overall and safe during pregnancy, and will prevent any potential depletion of glutathione stores" ([source](https://news.ycombinator.com/item?id=45886242)) "generally it's a safe thing with a low chance of making anything worse" ([source](https://news.ycombinator.com/item?id=47859449))
- Helps with hangovers and alcohol damage (2 comments): "It's also very effective at helping reduce the damage of alcohol, if you take it before drinking." ([source](https://news.ycombinator.com/item?id=46451591)) "the effect is clear and reproducible. My hangovers are also less bad." ([source](https://news.ycombinator.com/item?id=47862901))
- Many studies across conditions (3 comments): "it has racked up papers showing its efficacy in a truly staggering number of illnesses and conditions" ([source](https://news.ycombinator.com/item?id=46450663)) "Highly recommend reading the actual literature on its effects" ([source](https://news.ycombinator.com/item?id=46450838)) "Read the molecular biology papers." ([source](https://news.ycombinator.com/item?id=46452579))
- Personal experiences of benefit (2 comments): "it helps with brain fog also! Plus it reduces stress and irritability." ([source](https://news.ycombinator.com/item?id=48790367)) "I used NAC supplement for 1 year and it changed my life" ([source](https://news.ycombinator.com/item?id=46494497))

## What people warn about

- Possible liver damage after drinking (2 comments): "post-treatment with NAC aggravated ethanol-induced hepatic lipid peroxidation and worsened acute ethanol-induced liver damage" ([source](https://news.ycombinator.com/item?id=46456423)) "can actually do more liver damage if taken after drinking than just taking nothing" ([source](https://news.ycombinator.com/item?id=49453423))
- Long-term safety data limited (2 comments): "research about the safety of taking NAC every day for the long term is limited" ([source](https://news.ycombinator.com/item?id=47860656)) "Taking it for a long time can reduce these levels, creating multiple secondary problems." ([source](https://news.ycombinator.com/item?id=46454733))
- Cancer risk in mouse study (2 comments): "One of the side effects in a study in mice was inducing lung cancer" ([source](https://news.ycombinator.com/item?id=47860690)) "NAC causes cancer in humans." ([source](https://news.ycombinator.com/item?id=45890474))

## Alternatives hackers recommend

- [Creatine monohydrate](https://hackerapproved.com/p/creatine.md): 104 recommend
- [Melatonin](https://hackerapproved.com/p/melatonin.md): 43 recommend
- [Magnesium glycinate](https://hackerapproved.com/p/magnesium-glycinate.md): 31 recommend
- [Psyllium husk](https://hackerapproved.com/p/psyllium-husk.md): 13 recommend
- [Magnesium L-threonate](https://hackerapproved.com/p/magnesium-l-threonate.md): 9 recommend

## Cite as

Hacker Approved, "N-acetylcysteine (NAC) supplement", https://hackerapproved.com/p/n-acetylcysteine/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).