Niacin: chemical forms, bioavailability, and health effects.
Elevated low-density lipoprotein cholesterol (LDL-C) has been the main target of lipid-altering therapy to reduce cardiovascular risk associated with dyslipidemia. Residual cardiovascular risk remains, however, after achievement of goal LDL-C levels and is associated in part with other risk markers of cardiovascular disease, including low high-density lipoprotein cholesterol (HDL-C), high lipoprotein a, and hypertriglyceridemia. Niacin is considered a valuable agent for therapy to modify high LDL-C as well as low HDL-C, high lipoprotein a, and hypertriglyceridemia. The forms of niacin available in the marketplace include unbound niacin, or free nicotinic acid (NA); extended-release NA, a form of NA that is released gradually over a period of time; inositol hexanicotinate, six molecules of NA covalently bonded to one molecule of inositol; and nicotinamide, or niacinamide, the amide form of NA, which is readily bioavailable. This review is designed to assist healthcare professionals in evaluating the form(s) of niacin best suited for a particular therapeutic goal. Further, it provides a literature-based evaluation of risk for NA, extended-release NA, inositol hexanicotinate, and nicotinamide.
Council for Responsible Nutrition, Washington, DC 20036, USA. dmackay@crnusa.org
Douglas
D
MacKay
John
J
Hathcock
Erminia
E
Guarneri
D001682:Biological Availability; D002318:Cardiovascular Diseases / Q000097:blood* / Q000517:prevention & control*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004305:Dose-Response Relationship, Drug; D050171:Dyslipidemias / Q000188:drug therapy; D006801:Humans; D000960:Hypolipidemic Agents / Q000009:adverse effects / Q000737:chemistry / Q000493:pharmacokinetics / Q000627:therapeutic use; D009525:Niacin / Q000009:adverse effects / Q000737:chemistry* / Q000493:pharmacokinetics* / Q000627:therapeutic use
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D000960:Hypolipidemic Agents; D009525:Niacin