Are dietary supplements with doses of 200-500mg of Niacin safe?

The use of high doses of Niacin (or vitamin B3, or vitamin PP) should be consulted with a doctor. The recommended niacin doses are 16 mg/day for men and 14 mg/day for women. Your doctor may recommend taking niacin if you have a health condition or deficiency of this vitamin. Although excess niacin is excreted in the urine, prolonged use can cause side effects such as redness of the face, gastrointestinal problems. Most healthy people get enough niacin in their diet, so additional supplementation of this vitamin is usually not needed. Vitamin PP can affect both the skin and the proper functioning of the nervous system, but the deficiency must be confirmed by research. More about Niacin: https://www.gdziepolek.pl/substancje/niacyna