evidence: Activated charcoal is often used to treat poisoning or overdose and may also treat diarrhea and lower cholesterol. Many people use it as a home remedy for various concerns, but little scientific evidence supports its other suggested benefits. [...] - Gas reduction. One recent study reports that taking activated charcoal 8 hours before an abdominal ultrasound significantly reduces the amount of gas in your gut, making it easier to get a clear ultrasound image. Still, more research is needed ( 24 ). - Diarrhea aid. One case study indicates that activated charcoal may help treat diarrhea, but higher quality studies are necessary ( 25 ). - Water filtration. Activated charcoal may help filter water by removing contaminants, suspended solids, and microorganisms like bacteria — all without affecting the water’s pH or taste ( 26 ). - Tooth whitening. This substance is anecdotally said to whiten teeth when used as a mouth rinse or in toothpaste. It’s said to do so by absorbing plaque and other teeth-staining compounds. However, no studies support this claim ( 27 ). - Hangover prevention. Activated charcoal is sometimes touted as a hangover cure. However, this substance doesn’t effectively absorb alcohol, so this benefit is very unlikely ( 3 ). - Skin treatment. Applying this substance to your skin is said to treat acne, dandruff, and insect or snake bites. Yet, almost no evidence supports these claims ( 28 ).