Niacinamide (Nicotinamide)

NAD precursorSkinBone

The no-flush form of vitamin B3. Cheap NAD+ precursor, evidence-backed for skin cancer prevention, and a quiet workhorse for joint and bone support.

EvidenceStrong (skin cancer prevention)

Strong for non-melanoma skin cancer prevention in high-risk individuals (ONTRAC trial). Moderate for: osteoarthritis pain reduction, acne (topical), hyperpigmentation, and inflammatory skin conditions. Modest NAD+ raising — less efficient than NMN/NR per dose but vastly cheaper. Effects: 4–12 months for skin cancer prevention.

Niacinamide (a.k.a. nicotinamide) is the amide form of vitamin B3, distinct from nicotinic acid (niacin) — niacinamide doesn't cause flushing or lipid changes. It's a precursor to NAD+ via the salvage pathway, supports DNA repair (by inhibiting PARP1, sparing NAD+ for other uses), and has demonstrated benefit in skin cancer prevention. The ONTRAC trial showed 23% reduction in non-melanoma skin cancers with 500 mg twice daily in high-risk patients — making niacinamide one of the very few supplements with rigorous outcome-trial data for cancer prevention. Topically, it's a workhorse skincare ingredient for acne, hyperpigmentation, and barrier support.

Form
Nicotinamide / Niacinamide — same compound, different naming. Plain capsules. Topical niacinamide serum (4–10%) is a separate use case for skin.
Dose
500 mg twice daily (1 g/day) — the ONTRAC dose for skin cancer prevention. 50–500 mg/day for general NAD+ / methylation support. Don't exceed 3 g/day chronically (liver risk).
Timing
With food (reduces nausea). AM and PM split for higher doses.
Schedule
Daily.
Side effects
Generally well-tolerated. Nausea, GI upset, headache, fatigue at high doses. Liver function changes at very high doses (>3 g/day).
Interactions
Mild interaction with anticoagulants. Carbidopa (Parkinson's) — some interaction reported. Does NOT cause flushing like niacin does.
Contraindications
Active liver disease. Caution at high doses with diabetes (paradoxical effect on glucose at high doses in some studies).
Lab markers
Liver enzymes (ALT, AST) if running >1 g/day long-term. NAD+ if tracking longevity protocol.
Food sources
Beef, chicken, turkey, salmon, tuna, mushrooms, peanuts, brown rice, fortified grains. Adequate dietary intake is easy.

Pairs with

TMG (betaine) — methylation support. NMN, NR (alternative NAD+ pathway). Topical niacinamide pairs with retinoids, vitamin C, hyaluronic acid in skincare.