The analysis of NHANES data found no evidence of an inverse association between dietary niacin intake and the risk for cardiovascular disease mortality.
Two breakdown products from excess niacin, called 2PY and 4PY, were strongly associated with myocardial infarction, stroke, and other adverse cardiac events in multiple analyses.
Although nicotinamide is often recommended, when it was put to the test, it had no efficacy in preventing nonmelanoma skin cancers among transplant recipients.