NAC: What It Is, Forms, Cautions, and Clean Brands

NAC is N-acetyl cysteine, a form of the amino acid cysteine. It supports your body’s production of glutathione, a key antioxidant.*

Forms and what to look for on the label

Plain capsules from a tested brand are usually enough.

Before you take it

It has a strong sulfur smell, which is normal. Talk to your doctor if you have asthma or take nitroglycerin.