We use essential cookies (authentication, your saved goals/stack) by default. With your permission we'll also enable privacy-respecting analytics (Vercel Web Analytics, anonymous load-time metrics) and error-replay diagnostics (Sentry — DOM snapshots only when an error fires) so we can fix bugs faster. Learn more about cookies
Nicotinamide (Niacinamide, Vitamin B3)
The amide form of vitamin B3 and a NAD+ precursor. Unlike the NAD+-longevity story, its strongest evidence is dermatologic: a Phase-3 RCT showed it cuts new non-melanoma skin cancers and actinic keratoses in high-risk patients, and it has long been used for acne. The NAD+/anti-aging rationale is real but unproven in humans.
What the evidence says
Nicotinamide helped in about half (2/3) of the studies that measured an effect — promising, but not unanimous.
Most evidence is from high-quality randomised trials published 1995–2026 with a typical study size of 100 participants.
Based on 7 studies · 5 RCTs · 898 total participants
Confidence
ModerateWhat the studies found
By outcome
Nicotinamide has an evidence score of 5.5/10 — moderate evidence based on 7 indexed studies. The amide form of vitamin B3 and a NAD+ precursor. Unlike the NAD+-longevity story, its strongest evidence is dermatologic: a Phase-3 RCT showed it cuts new non-melanoma skin cancers and actinic keratoses in high-risk patients, and it has long been used for acne. The NAD+/anti-aging rationale is real but unproven in humans. Representative study: PMID 26488693.
The commonly studied dose of Nicotinamide is 500mg twice daily. Research points to an estimated optimal dose around 1000mg, with a minimum effective dose near 500mg. Individual response varies — start low and adjust.
Notable regimens that report including Nicotinamide — documented, not endorsed.
Explore: Best supplements for Body HealthBest supplements for Vitality & LongevityBest supplements for Focus, Memory & Mood
Last reviewed June 2026 · evidence from 7 studies · how we score
This information is for educational purposes only. It is not a substitute for professional medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any supplement or medication.
A Phase-3 RCT (ONTRAC) gives nicotinamide genuinely strong evidence for one outcome — reducing new non-melanoma skin cancers and actinic keratoses in high-risk patients — plus older dermatology RCTs for acne. But the broader NAD+/anti-aging rationale is mechanistic and unproven in humans, the renal/phosphate trials are mixed and tolerability-limited, and cognition was null even within ONTRAC, holding the overall score to Moderate.
Nicotinamide (niacinamide) is the amide form of vitamin B3 and a direct precursor to NAD+, the coenzyme central to cellular energy metabolism and DNA repair. Unlike niacin (nicotinic acid), it does not cause flushing and has a far weaker effect on lipids.
Its best human evidence is in dermatology rather than longevity: the Phase-3 ONTRAC randomized trial showed that 500 mg twice daily reduced the rate of new non-melanoma skin cancers by 23% and actinic keratoses by ~13-20% in high-risk patients with prior skin cancers — a genuinely landmark chemoprevention result.
Topical and oral niacinamide also have a long history in acne, where a classic RCT found 4% nicotinamide gel comparable to clindamycin.
The NAD+-precursor angle is mechanistically plausible — nicotinamide replenishes NAD+, the substrate for PARP-driven DNA repair and sirtuin signaling, both relevant to UV-damaged skin and aging — but, as with NMN and NR, a human longevity or healthspan benefit from raising NAD+ remains unproven.
It is well tolerated at normal doses; high doses can cause GI upset and, rarely, hepatotoxicity (less than niacin), and renal/dialysis phosphate-binding trials have been mixed and tolerability-limited.
An honest, useful, inexpensive supplement with one strong proven use (skin-cancer chemoprevention) and a speculative longevity rationale.
Enters the NAD+ salvage pathway, replenishing the NAD+ pool that fuels cellular energy and repair
Provides NAD+ as substrate for PARP enzymes that repair UV-induced DNA damage in skin
Prevents UV-induced ATP depletion and immunosuppression, the basis of its skin-cancer chemoprevention
How Nicotinamide works — from molecular targets to health outcomes. Click an edge to see supporting research.This visualization is in beta — pathways are being refined and expanded.
Tap node to isolate • Pinch to zoom • Tap edge for research
500mg twice daily
Take with food
| Form | Type |
|---|---|
| 💊Niacinamide tablets (500mg) | Recommended |
| 🧴Topical niacinamide gel/serum (for acne/cosmetic use) | Alternative |
Choose niacinamide (nicotinamide), not nicotinic acid (niacin), to avoid flushing. Inexpensive and widely available; look for third-party tested products.
Minimum: 12 weeks
Optimal: 52 weeks
Cycling: Not required
Note: The chemoprevention evidence used 500 mg twice daily. Splitting morning/evening with food keeps levels steady and minimizes nausea.
The ONTRAC RCT used 500 mg twice daily (1000 mg/day total) and reduced new non-melanoma skin cancers by 23%. Effect requires continuous use; it disappeared after discontinuation. Curve is indicative — only the 1000 mg/day regimen is directly RCT-supported.
Reduces new non-melanoma skin cancers and actinic keratoses in high-risk patients
Topical and oral niacinamide reduce inflammatory acne lesions
Raises NAD+ via the salvage pathway; downstream longevity benefit unproven in humans
Nausea or stomach upset can occur at gram-level doses
Vitamin B3 is required in pregnancy at RDA levels; high supplemental doses are not established — stay within normal intake unless directed
Used investigationally as a phosphate binder but tolerability is poor at high doses (NICOREN); use only under nephrology supervision
Avoid gram-level chronic dosing; monitor liver enzymes
High-dose nicotinamide may inhibit hepatic metabolism of some drugs; monitor with anticonvulsants at gram-level doses
Tip: Take with food; lower the dose
Tip: Avoid gram-level chronic dosing without monitoring; far less hepatotoxic than niacin
Tip: Seen in the NICOREN dialysis trial at gram-level doses; monitor platelets in renal use
Both are vitamin B3 forms that raise NAD+ through overlapping salvage/Preiss-Handler routes; nicotinamide is the cheaper, simpler precursor.
Redundant rather than additive for NAD+ — choose based on cost and intended outcome
NMN and nicotinamide both feed the NAD+ pool; nicotinamide is recycled from NAD+ consumption and re-enters via the salvage pathway.
Shared NAD+ pathway — overlapping rather than strongly synergistic
The best time to take Nicotinamide is with meals. Taking it with food is preferred. Nicotinamide is water-soluble and well absorbed orally; taking it with food reduces the mild GI upset that can occur at higher doses.
Nicotinamide is generally well-tolerated and considered safe for most healthy adults at recommended doses. The most commonly reported side effects are nausea / GI upset, elevated liver enzymes (high doses), thrombocytopenia (high-dose, dialysis use). Use caution if any of these apply to you: Known hypersensitivity to niacin/niacinamide; Severe hepatic impairment (caution at high doses).
Fat-soluble vitamin that maintains night vision, drives immune cell differentiation, and regulates skin turnover and cellular growth.