# Nicotinamide

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/nicotinamide
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-02
**Evidence Score:** 4 / 10
**Category:** Vitamin
**Also Known As:** Niacinamide, Vitamin B3 amide, Nicotinic acid amide, 3-Pyridinecarboxamide, Vitamin PP amide, NAM, Pyridine-3-carboxamide, Nicotinamide

## Overview

Nicotinamide (niacinamide) is the amide form of vitamin B3 that serves as a precursor to NAD+ and NADP+, coenzymes critical for DNA repair, [energy metabolism](/ingredients/condition/energy), and cellular signaling. Unlike nicotinic acid, it does not activate GPR109A receptors, so it delivers therapeutic effects without causing skin flushing.

## Health Benefits

• Reduces non-melanoma skin cancers by 23% in high-risk patients (Strong evidence: Phase 3 RCT, n=386, PMID: 26488693)
• Decreases actinic keratoses by 11-20% over 12 months (Strong evidence: Phase 3 RCT, PMID: 26488693)
• Lowers squamous cell carcinoma risk by 30% (Moderate evidence: Phase 3 RCT, PMID: 26488693)
• Enhances DNA repair and reduces UV-induced immunosuppression (Mechanistic evidence from clinical trials)
• Supports cellular [energy metabolism](/ingredients/condition/energy) through NAD+ production (Preliminary evidence: related [NAD+ precursor](/ingredients/condition/longevity) studies)

## Mechanism of Action

Nicotinamide is converted intracellularly to NAD+ via the salvage pathway, where nicotinamide phosphoribosyltransferase (NAMPT) catalyzes its conversion to nicotinamide mononucleotide (NMN), which is subsequently adenylated by NMNAT enzymes. Elevated NAD+ activates PARP-1 and PARP-2, enzymes that repair UV-induced DNA strand breaks, and also fuels [sirtuin](/ingredients/condition/longevity)s (SIRT1–SIRT7), deacetylases that regulate [inflammation](/ingredients/condition/inflammation) and genomic stability. Additionally, nicotinamide inhibits poly-ADP-ribose polymerase overactivation that would otherwise deplete NAD+ stores during [oxidative stress](/ingredients/condition/antioxidant), preserving cellular energy reserves.

## Clinical Summary

The strongest evidence comes from a Phase 3 RCT (n=386, PMID: 26488693) in high-risk patients, demonstrating that 500 mg twice-daily oral nicotinamide reduced new non-melanoma skin cancers by 23%, actinic keratoses by 11–20%, and squamous cell carcinoma incidence by approximately 30% over 12 months compared to placebo. These benefits disappeared within 6 months of discontinuation, indicating the effect requires sustained supplementation. Dermatological evidence is rated strong given the double-blind, placebo-controlled design and clinically meaningful effect sizes. Evidence for other proposed benefits — including [glucose metabolism](/ingredients/condition/weight-management), [inflammatory](/ingredients/condition/inflammation) skin conditions, and osteoarthritis — is generally rated moderate to weak, drawn from smaller or shorter trials with less consistent outcomes.

## Nutritional Profile

Nicotinamide (niacinamide) is the amide form of vitamin B3 (niacin), with a molecular weight of 122.12 g/mol. It is a water-soluble vitamin that serves as the precursor to nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+), two critical coenzymes involved in over 400 enzymatic reactions. Standard supplemental doses range from 500 mg to 1500 mg/day (typically 500 mg twice or thrice daily for skin cancer chemoprevention). Oral bioavailability is high (~100%), rapidly absorbed in the small intestine, with peak plasma levels reached within 1-2 hours. Unlike nicotinic acid, nicotinamide does not cause flushing at therapeutic doses. It contains no macronutrients, fiber, or minerals—it is a pure bioactive compound. Hepatic [metabolism](/ingredients/condition/weight-management) converts nicotinamide to NAD+ via the salvage pathway enzyme nicotinamide phosphoribosyltransferase (NAMPT). Excess is methylated to N-methyl-nicotinamide and further oxidized metabolites excreted renally. Dietary sources include poultry (~12 mg/100g), tuna (~8.6 mg/100g), beef liver (~16 mg/100g), and fortified cereals, though chemoprevention doses far exceed dietary intake (~15-20 mg NE RDA).

## Dosage & Preparation

Clinically studied doses use oral tablets or powder: 500 mg twice daily (1000 mg total) for skin cancer prevention, based on the ONTRAC trial. Some patients require dose reduction to 500 mg once daily due to gastrointestinal tolerability. Studies used pharmaceutical-grade nicotinamide without standardization beyond purity. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Nicotinamide is generally well tolerated at supplemental doses up to 1,500 mg/day, with nausea, headache, and mild gastrointestinal upset reported at higher doses; hepatotoxicity has been observed with chronic use above 3,000 mg/day. Unlike nicotinic acid, it does not cause [prostaglandin](/ingredients/condition/inflammation)-mediated flushing, making it preferable for patients who cannot tolerate that form. Clinically relevant drug interactions include potentiation of anticonvulsants (e.g., carbamazepine, valproate) and potential additive effects with insulin or sulfonylureas on glucose regulation. Nicotinamide is considered safe during pregnancy at dietary intake levels (RDA: 18 mg NE/day for pregnant women), though high-dose supplementation during pregnancy lacks robust safety data and should be avoided without medical supervision.

## Scientific Research

The landmark ONTRAC Phase 3 RCT (PMID: 26488693) demonstrated nicotinamide's efficacy in 386 high-risk patients, showing 23% reduction in new non-melanoma skin cancers. A meta-analysis (PMID: 37994989) pooled 4 RCTs but found mixed results, with clearer benefits for squamous cell carcinoma prevention. A pilot study in kidney transplant recipients (PMID: 37838527) showed limited efficacy with tolerability issues at higher doses.

## Historical & Cultural Context

No historical traditional medicine use was documented in the research. Nicotinamide is a modern synthetic form of vitamin B3, studied primarily in contemporary clinical contexts rather than ethnobotanical systems. Its use emerged from 20th-century nutritional science and vitamin research.

## Synergistic Combinations

Nicotinamide pairs well with broad-spectrum sunscreen (SPF 50+), which provides additive [photoprotect](/ingredients/condition/skin-health)ion—nicotinamide enhances cellular DNA repair (boosting nucleotide excision repair by ~20-40%) while sunscreen blocks UV penetration, together reducing actinic keratoses more than either alone. Combining with zinc (30 mg/day as zinc picolinate) supports poly(ADP-ribose) polymerase (PARP) activity—a zinc-finger DNA repair enzyme that consumes NAD+—ensuring both the cofactor (NAD+ from nicotinamide) and the structural mineral (zinc) are available for optimal DNA damage response. Vitamin D3 (1000-2000 IU/day) complements nicotinamide's immunoprotective effects, as UV avoidance strategies often reduce endogenous vitamin D synthesis, and vitamin D itself has anti-proliferative effects on keratinocytes. Additionally, sulforaphane (from broccoli seed extract, ~30 mg/day) upregulates Nrf2-mediated [antioxidant](/ingredients/condition/antioxidant) defenses and [phase II detox](/ingredients/condition/detox)ification enzymes, providing a complementary chemopreventive mechanism alongside nicotinamide's NAD+-dependent energy and repair pathways. Resveratrol (150-250 mg/day) may further synergize by activating [sirtuin](/ingredients/condition/longevity)s (SIRT1/SIRT3), NAD+-dependent deacetylases that regulate cellular [stress response](/ingredients/condition/stress)s, though nicotinamide itself is a weak sirtuin inhibitor at high concentrations, so moderate dosing of both is advisable.

## Frequently Asked Questions

### What is the recommended dosage of nicotinamide for skin cancer prevention?

The dosage used in the landmark Phase 3 RCT (PMID: 26488693) was 500 mg taken twice daily (1,000 mg/day total) for 12 months in immunocompetent patients with a history of at least two non-melanoma skin cancers. This dose produced a 23% reduction in new skin cancer cases and a 11–20% reduction in actinic keratoses. Benefits were not maintained after stopping supplementation, so continuous use appears necessary for sustained protection.

### What is the difference between nicotinamide and niacinamide?

Nicotinamide and niacinamide are identical compounds — both names refer to the amide form of vitamin B3 (pyridine-3-carboxamide), with 'niacinamide' being the name more commonly used in cosmetic and topical product labeling. Both are distinct from nicotinic acid (plain niacin), which activates the GPR109A receptor and causes vasodilatory skin flushing at therapeutic doses. Nicotinamide/niacinamide does not activate GPR109A, so it lacks the flushing side effect while still serving as an NAD+ precursor.

### Does nicotinamide raise NAD+ levels effectively compared to NMN or NR?

Nicotinamide raises intracellular NAD+ via the salvage pathway through NAMPT-mediated conversion to NMN, the same intermediate produced directly by NMN supplementation. Human pharmacokinetic studies suggest nicotinamide is efficiently converted to NAD+ at doses of 500–1,000 mg/day, though at very high doses it can accumulate as methylated metabolites (1-methylnicotinamide) that may exert independent biological effects. Comparative head-to-head trials between nicotinamide, NMN, and nicotinamide riboside (NR) in humans are limited, but cost per milligram of NAD+ precursor strongly favors nicotinamide.

### Can nicotinamide be applied topically for skin benefits?

Yes, topical nicotinamide at concentrations of 2–5% is widely used in dermatology and is supported by multiple RCTs demonstrating reductions in hyperpigmentation, sebum production, transepidermal water loss, and inflammatory acne lesions. A 2% topical nicotinamide formulation was shown in a double-blind study to reduce acne severity comparably to 1% clindamycin gel. The mechanism involves inhibition of melanosome transfer to keratinocytes (reducing pigmentation), upregulation of ceramide synthesis (strengthening the skin barrier), and suppression of pro-inflammatory cytokines including IL-8 and TNF-alpha.

### Is nicotinamide safe to take with metformin or other diabetes medications?

Nicotinamide at high doses (above 1,000 mg/day) may modestly impair insulin sensitivity by inhibiting SIRT1-mediated regulation of hepatic glucose output and by reducing beta-cell PARP activity, which has shown mixed effects on glucose metabolism in clinical studies. Patients on metformin, insulin, or sulfonylureas should monitor blood glucose if initiating doses above 500 mg/day, as additive hypoglycemic or antagonistic effects are both theoretically possible depending on metabolic context. No formal pharmacokinetic interaction between nicotinamide and metformin has been established, but prescribers typically recommend periodic HbA1c monitoring in diabetic patients using high-dose nicotinamide long-term.

### What is the clinical evidence quality for nicotinamide's skin cancer prevention benefits?

Nicotinamide has strong clinical evidence from a Phase 3 randomized controlled trial (n=386) demonstrating a 23% reduction in non-melanoma skin cancers and 30% reduction in squamous cell carcinoma risk in high-risk patients. The same study showed an 11-20% decrease in actinic keratoses over 12 months, providing robust evidence for its protective effects. These results are supported by mechanistic studies showing nicotinamide enhances DNA repair and reduces UV-induced immunosuppression.

### Who should consider taking nicotinamide supplementation for skin health?

Individuals with high risk for non-melanoma skin cancers—including those with a history of skin cancer, chronic sun exposure, or actinic keratoses—are primary candidates for nicotinamide supplementation based on clinical evidence. People with fair skin, outdoor occupations, or those living in sunny climates may also benefit from its protective effects. However, supplementation decisions should be made in consultation with a dermatologist to assess individual risk factors and whether oral nicotinamide is appropriate for your specific situation.

### How does nicotinamide prevent skin cancer at the cellular level?

Nicotinamide works through two primary mechanisms: it enhances DNA repair pathways that are damaged by UV exposure, and it reduces UV-induced immunosuppression that normally allows damaged cells to proliferate unchecked. By restoring immune function in sun-damaged skin and improving cellular repair capacity, nicotinamide helps prevent the accumulation of mutations that lead to non-melanoma skin cancers and actinic keratoses. This dual action makes it particularly effective as a preventive supplement for individuals with significant sun exposure history.

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