The fight between the dietary supplement industry and FDA over the ingredient NAC will heat up in 2022: 2022 Ingredient trends for food, drinks, dietary supplements, and natural products Nutritional Outlook N Acetyl L Cysteine (NAC), 600 mg, 60 capsules N acetylcysteine (NAC) is a supplement I frequently recommend to clients most commonly for conditions such as endometriosis or as part of post concussion protocols. Some of you might also recognise NAC Acetyl L Carnitine