There are various forms of niacin out there, a few are nicotinic acid (NA), nicotinamide/niacinamide (NAM), nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR). Nicotinic acid has a few side effects, such as flushing, nausea, fainting and can even cause insulin resistance and liver toxicity and exacerbate peptic ulcer disease, which NAM doesn’t have. (1, 2) B3 … Read more