Niacin is an essential vitamin at small doses and a drug-like agent at large ones. It reliably improves blood fats and lowers a stubborn, genetically driven risk particle, but recent large studies found no reduction in heart attacks or strokes when added to modern cholesterol treatment, plus real harms. Its longevity case remains theoretical. (Full Review)

Protocol

Standard Dose

1–2 g/day

Titrated over 4–8 weeks from 100–250 mg; occasionally up to 3 g

Formulation

Immediate-release

Or prescription extended-release at bedtime; avoid sustained-release

Dosing Pattern

Split with meals

Immediate-release split 2–3×/day; extended-release once at bedtime

Time to effect

Lipid Changes

4–8 weeks

After reaching an effective dose

Flushing

Immediate

Wanes over days to weeks of consistent use

Benefits

High: Corrects niacin deficiency and prevents pellagra; improves atherogenic lipid profile

Medium: Reduction of lipoprotein(a)

Low: Cardiovascular event reduction; slowing of atherosclerosis progression

Speculative: NAD+ restoration for cellular aging and longevity; neuroprotection and cognitive support

Contraindications

Active liver disease or transaminases > 3× upper limit of normal

Active peptic ulcer disease

Poorly controlled diabetes (HbA1c > 8%)

Recent bleeding event or stroke (within ~3 months)

Gout

Pregnancy or breastfeeding at pharmacologic doses

Unstable cardiovascular disease (acute coronary syndrome within ~90 days)

Key Interactions

Statins (simvastatin, atorvastatin, rosuvastatin)

Antidiabetic drugs (metformin, insulin, sulfonylureas)

Blood-pressure-lowering and vasodilating drugs (calcium channel blockers, nitrates, alpha-blockers)

Anticoagulants and antiplatelets (warfarin, apixaban, aspirin, clopidogrel)

Bile acid sequestrants (cholestyramine, colesevelam)

Alcohol and hot beverages

Additive supplements (red yeast rice, berberine, high-dose omega-3s, chromium)

Risk & Side Effects

High: Skin flushing; hepatotoxicity; new-onset diabetes and worsened glycemic control; hyperuricemia and gout

Medium: Gastrointestinal upset and peptic ulcer aggravation; increased infection and bleeding risk

Low: Niacin maculopathy; myopathy in combination with statins

Speculative: Harm from terminal metabolites

Monitoring

Marker	Target	Why
Triglycerides	< 80 mg/dL	Primary lipid target niacin lowers
HDL cholesterol	> 50 mg/dL (women), > 40 mg/dL (men)	Tracks HDL-raising effect
Lp(a)	< 30 mg/dL (< ~75 nmol/L)	The niche biomarker niacin can lower
ApoB	< 80 mg/dL (aggressive: < 60)	Best overall marker of atherogenic particles
AST / ALT (liver enzymes)	< 30 U/L	Detects hepatotoxicity early
Fasting glucose	70–90 mg/dL	Detects niacin-induced glucose rise
HbA1c	< 5.4%	Tracks longer-term glycemic impact
Uric acid	< 5.5 mg/dL	Flags hyperuricemia and gout risk

Cadence: Every 6–12 weeks during titration, then every 3–6 months once stable; recheck after any dose increase

Qualitative Assessment

Presence, intensity, and trend of flushing
Energy levels and exercise tolerance
Any muscle aches (possible myopathy signal, especially with a statin)
Visual changes (rare maculopathy signal)
Digestive comfort and appetite

Niacin for Health & Longevity

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment