Niacin (nicotinic acid) is the most effective supplement for raising HDL cholesterol — increasing it by 20-35% at therapeutic doses of 1-3g/day. However, two landmark trials (AIM-HIGH and HPS2-THRIVE) found that adding niacin to statin therapy provided NO cardiovascular outcome benefit while increasing adverse events. The "niacin flush" (flushing, itching, warmth) affects 85% of users and is the primary reason for discontinuation. Our research distinguishes between nicotinic acid (flush-causing, lipid-active), niacinamide (no flush, no lipid effect), and nicotinamide riboside/NMN (NAD+ precursors — completely different mechanism).
Niacin acts on the GPR109A receptor in adipose tissue, reducing lipolysis (free fatty acid release). With fewer free fatty acids reaching the liver, VLDL production decreases → triglycerides drop 20-50% → and as a consequence, HDL increases 20-35%. The flush is also mediated by GPR109A — it triggers prostaglandin D2 release in skin, causing vasodilation, warmth, and itching. Extended-release formulations slow the peak activation, reducing flush. At RDA doses, niacin serves as a precursor to NAD+/NADH, essential for 400+ enzymatic reactions.
Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.