Niacin (Nicotinic Acid) · Evidence-First Lite Reference
Niacin (Nicotinic Acid) Lite reference · evidence-first overview + FAQ. Educational only.
Overview
This is a Lite reference page for Niacin (Nicotinic Acid). For deep evidence (mechanism, dose-response, full PMID citations), please consult primary literature and the cross-linked references on related goal/lifestyle pages.
Tags
Body Systems: METABOLISM · Cardiovascular · Skin & Connective Tissue
Mechanisms: NAD+ precursor · HM74A/GPR109A agonism
Evidence Tier: lite-tier-c
Layer: B (Lite reference)
Frequently Asked Questions
The questions below cover the most common questions on Niacin (Nicotinic Acid). This is an evidence-first Lite reference page; for deep mechanism narratives, dose-response analyses, and full PMID citations please consult primary literature. Answers below intentionally disclose evidence-base limitations rather than overstate the supplement category.
1. What is niacin?
Niacin, or nicotinic acid, is the acid form of vitamin B3. At nutritional intakes it supports vitamin B3 adequacy and NAD+ biology; at pharmacologic gram-level exposure it has historically been used in lipid-management settings under medical supervision.
2. What do AIM-HIGH and HPS2-THRIVE mean for niacin claims?
AIM-HIGH 2011 (PMID 22085343) and HPS2-THRIVE 2014 (PMID 25014686) are the key caution anchors: adding high-dose niacin therapy on a statin background did not produce the expected incremental vascular benefit and introduced adverse-event concerns. This Lite page therefore links niacin to /goals/heart-health/ with conservative language rather than broad cardiovascular claims.
3. Why does niacin cause flushing?
Nicotinic acid activates HM74A/GPR109A, which can trigger prostaglandin-mediated flushing. This is a pharmacologic effect of niacin and should not be generalized to niacinamide.
4. What dose frame is used here?
The public card separates 14-18 mg/day vitamin B3 adequacy from 500-2000 mg/day extended-release prescription niacin. Non-prescription high-dose use is constrained by the 35 mg/day adult UL for flushing risk and by liver-safety concerns at sustained gram-level exposure.
5. Where does this page sit in the evidence library?
This is a Lite reference page. For deeper evidence please consult primary literature on low-dose nutrient adequacy, prescription lipid pharmacology (AIM-HIGH + HPS2-THRIVE anchors), flushing and hepatotoxicity boundaries, and jurisdiction-specific authorized vitamin-B3 family claims.