Vitamin B3 (Niacin / Nicotinamide)

Niacin (vitamin B3) is the umbrella term for nicotinic acid and nicotinamide — two forms that share the same vitamin activity but have different non-vitamin properties. Both are precursors of NAD⁺ and NADP⁺, the universal redox cofactors of cellular energy metabolism. UK NRV is 16 mg niacin equivalents (NE)/day. Six authorised UK Article 13.1 health claims apply at ≥15 % NRV. Pharmacological-dose nicotinic acid (500–2,000 mg/day) for lipid modification is a different intervention with prescribing-tier side effects (flushing, hepatotoxicity) — not relevant to typical food-supplement use.

Camden Medicals editorial · Last reviewed 12 June 2026 · Next review June 2027

  • Cross-checked against
  • NHS
  • NICE
  • BNF
  • EFSA
  • FSA
Verifera Evidence ReviewCamden’s own editorial review · evidence-graded, verification in progress — graded, not guessed.

Camden's own editorial team graded each health claim below on the strength of the published evidence — trials weighed with Cochrane RoB 2, systematic reviews with AMSTAR 2, under the CEGA method. See the grade beside every condition.

Class
Vitamin
Typical daily dose
NRV 16 mg/day. Common supplement doses 10–50 mg/day (typically nicotinamide). Pharmacological lipid-modifying nicotinic acid is 500–2,000 mg/day under medical supervision.
Top use evidence
Insufficient
On this page
  1. What it is
  2. At a glance
  3. What people use it for
  4. How it works
  5. Common myths
  6. Common online questions
  7. The official position
  8. Authorised UK claims
  9. What the guidance says
  10. Camden's evidence review
  11. Safety, interactions & who should avoid it
  12. How to take it
  13. How to spot quality
  14. Commonly combined with
  15. Related ingredients
  16. Sources

What it is

Niacin is the umbrella name for two molecules with vitamin B3 activity: nicotinic acid (the original "niacin") and nicotinamide (also called niacinamide). Both are precursors of nicotinamide adenine dinucleotide (NAD⁺) and its phosphorylated form NADP⁺ — the redox coenzymes that drive most of cellular energy metabolism, biosynthesis, DNA repair, and antioxidant defence.

The two forms share identical vitamin activity once incorporated into NAD⁺ but have different non-vitamin pharmacology. Nicotinic acid at pharmacological doses (500–2,000 mg/day) lowers LDL cholesterol and triglycerides and raises HDL — historically used as a lipid-modifying drug, now largely supplanted by statins — and produces a characteristic skin-flushing reaction at >50 mg via prostaglandin D2 release. Nicotinamide does not flush at any dose and lacks the lipid-modifying effect; it is the form used in non-flushing supplement labels and in dermatology research.

The body also synthesises niacin endogenously from the amino acid tryptophan (~60 mg tryptophan → 1 mg niacin). UK NRV is expressed as "niacin equivalents" (NE) to account for both dietary niacin and tryptophan-derived contribution.

Common supplement forms are nicotinamide (standard, non-flushing), nicotinic acid (lipid-context, flushing), and inositol hexanicotinate ("flush-free niacin", debated lipid efficacy). Nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN) are separate molecules with their own encyclopaedia entries — NAD⁺ precursors but technically distinct vitamers with different regulatory status.

At a glance

  • Vitamin B3 is the umbrella term for two interchangeable forms — nicotinic acid (flushing) and nicotinamide (non-flushing) — both precursors to the NAD⁺/NADP⁺ energy cofactors.
  • UK NRV is 16 mg niacin equivalents/day, generally well-supplied via meat, fish, fortified bread and peanuts.
  • 6 authorised UK Article 13.1 claims at ≥15% NRV: energy metabolism, nervous-system function, psychological function, mucous membranes, skin, and reduction of tiredness/fatigue.
  • High-dose nicotinic acid (≥500 mg/day) is a lipid-modifying drug with flushing + liver-toxicity risk — a prescribing decision, not a food-supplement use.

What people use it for

  • Adults seeking niacin at NRV intake for the authorised claim list

    At ≥15 % NRV (≥2.4 mg) the GB NHC register authorises 6 niacin claims covering energy metabolism, nervous-system function, psychological function, mucous-membrane and skin maintenance, and tiredness/fatigue reduction. [2]

    Popular, not provenInsufficient

  • Adults at low intake — restricted-meat diets, alcohol misuse, malabsorption

    Routine NRV-tier supplementation returns intake to target. Pellagra is rare in the UK; alcohol misuse is the most common at-risk context. [1]

    Popular, not provenInsufficient

  • People considering high-dose nicotinic acid for lipid modification

    This is a prescribing-tier decision, not a food-supplement use. Statins, ezetimibe, PCSK9 inhibitors, and bempedoic acid are first-line in UK lipid pathways. Nicotinic acid retains a niche specialist role. [3]

    Popular, not provenInsufficient

How it works

NAD⁺ accepts electrons in over 200 oxidation reactions across glycolysis, the TCA cycle, fatty-acid β-oxidation, and the pentose phosphate pathway. NADP⁺ provides reducing power for biosynthesis (cholesterol, fatty acids) and is the cofactor for glutathione reduction and other antioxidant pathways. Niacin deficiency therefore impairs energy generation, biosynthesis, and tissue repair — explaining the dermatological, GI, and neurological presentations of pellagra ("the 4 Ds": dermatitis, diarrhoea, dementia, death if untreated).

Common myths

Myth"Niacin flushing is the supplement working / cleansing toxins."

RealityIt is a prostaglandin D2-mediated cutaneous vasodilation. Not a "cleansing" effect. Flushing occurs with nicotinic acid; not with nicotinamide. The two forms share vitamin activity but not flushing pharmacology.

Myth"Niacin "cleans" arteries / reverses heart disease."

RealityPharmacological nicotinic acid modifies lipids modestly. Large outcome trials (AIM-HIGH, HPS2-THRIVE) failed to show cardiovascular event reduction when added to statins; safety signals (myopathy, GI bleeding, infection) led to UK / European de-emphasis. Statins remain first-line. [6,7,3]

Common online questions

Synthesised from the questions UK shoppers most often ask online about Vitamin B3 (Niacin / Nicotinamide). Each answer is editorial and links to its evidence in the Sources list below.

Niacin or nicotinamide — which form?

For routine food-supplement vitamin coverage, nicotinamide is the standard (no flushing). Nicotinic acid is the form used pharmacologically for lipid modification — at much higher doses, with flushing and hepatotoxicity considerations, and that is a prescribing decision not a supplement decision.

Is niacin flushing dangerous?

At pharmacological doses the flushing itself is uncomfortable but not dangerous. The bigger safety concerns at chronic high-dose nicotinic acid are hepatotoxicity, hyperuricaemia, and hyperglycaemia — reasons the cardiovascular use case has receded. Nicotinamide does not produce flushing.

⚖️ The official position

What may lawfully be claimed about Vitamin B3 (Niacin / Nicotinamide) in Great Britain. This is a regulatory position, not an evidence grade.

A health claim is authorised in Great Britain.

“Niacin contributes to normal energy-yielding metabolism”

“Niacin contributes to normal functioning of the nervous system”

“Niacin contributes to normal psychological function”

“Niacin contributes to the maintenance of normal mucous membranes”

“Niacin contributes to the maintenance of normal skin”

“Niacin contributes to the reduction of tiredness and fatigue”

This claim is authorised for use in Great Britain under the GB Nutrition and Health Claims regulation. A product may carry it when it provides at least 15% of the UK NRV per recommended daily portion.

Authorised UK health claims

Verbatim from the GB Nutrition and Health Claims Register (Reg 432/2012 as assimilated in GB). A product can carry these claims when it provides at least 15% of the UK NRV per recommended daily portion.

6 authorised claims — show / hide
  • "Niacin contributes to normal energy-yielding metabolism"
  • "Niacin contributes to normal functioning of the nervous system"
  • "Niacin contributes to normal psychological function"
  • "Niacin contributes to the maintenance of normal mucous membranes"
  • "Niacin contributes to the maintenance of normal skin"
  • "Niacin contributes to the reduction of tiredness and fatigue"

UK regulatory landscape

UK regulatory tier: Food supplement

EFSA claim status

Niacin is an Annex-listed nutrient with authorised Article 13.1 claims; not a botanical-on-hold ingredient.

UK regulatory rules evolve. This summary is editorial — businesses should consult regulatory counsel; consumers should consult their pharmacist or GP.

🩺 What the guidance says

What UK and international health bodies say. Guidance leads; Camden’s own evidence review follows below.

  • NHSConditional

    NHS — B vitamins and folic acid (niacin)

    The NHS states that most people can get all the niacin they need from a varied and balanced diet, and that niacin contributes to releasing energy from food and to a healthy nervous system and skin. It advises that taking high doses of nicotinic acid supplements can cause skin flushes, and that very high doses over a long time could lead to liver problems — so anyone who supplements should keep within sensible amounts and seek advice if unsure.

    Read the guidance →

  • GB-NHCConditional

    Great Britain Nutrition and Health Claims (NHC) Register — niacin

    Only health claims on the GB Nutrition and Health Claims Register may be made for a food supplement sold in Great Britain. The register authorises six niacin claims — covering normal energy-yielding metabolism, normal functioning of the nervous system, normal psychological function, maintenance of normal mucous membranes and skin, and reduction of tiredness and fatigue — each usable only where the product provides at least 15% of the nutrient reference value. No other health benefit may be claimed for niacin on a food-supplement basis.

    Read the guidance →

  • EFSARecommends

    EFSA — Scientific Opinion on the substantiation of health claims related to niacin (Article 13(1))

    The EFSA panel reviewed the science behind the niacin health claims and concluded that a cause-and-effect relationship is established between dietary niacin intake and normal energy-yielding metabolism, normal functioning of the nervous system, and the maintenance of normal skin and mucous membranes. These scientific opinions underpin the niacin claims later authorised for use in Great Britain.

    Read the guidance →

  • NICERecommends against

    NICE NG238 — Cardiovascular disease: risk assessment and reduction, including lipid modification

    NICE guideline NG238 advises clinicians not to offer nicotinic acid (niacin) to lower cardiovascular risk, because trials adding it to statin therapy did not reduce cardiovascular events. Statins are the first-line lipid-lowering treatment in the NHS. This is NHS prescribing guidance for a pharmacological intervention, not a food-supplement use.

    Read the guidance →

  • BNFConditional

    BNF — Nicotinic acid (indications, dose and prescribing information)

    Read the guidance →

  • SOCIETY-OTHERConditional

    British Association of Dermatologists — Nicotinamide for non-melanoma skin cancer

    The British Association of Dermatologists' patient information explains that nicotinamide (a form of vitamin B3) has been studied at 500 mg twice daily to lower the rate of new non-melanoma skin cancers in people at high risk, based mainly on Australian trial data, and notes the benefit continues only while the supplement is taken. It frames nicotinamide as a specialist option to discuss with a dermatologist, not a routine supplement, and notes the UK evidence is still limited.

    Read the guidance →

🔬 Camden’s evidence review

The research Camden reviewed, graded on its strength. This is our own appraisal — it sits beneath the official guidance above, never above it.

  1. Pellagra / niacin deficiency

    Evidencelimited

    The research Camden reviewed: niacin is a defined essential micronutrient with an established deficiency syndrome (pellagra), and replacement resolves its features — recent reviews report symptom resolution within roughly four weeks of vitamin B3 supplementation. Pellagra is rare in the modern UK; alcohol misuse, post-bariatric states, malabsorption and certain medicines (for example isoniazid) are the principal at-risk contexts. [8,9]

  2. Lipid modification (high-dose nicotinic acid)

    Evidencemoderate

    The research Camden reviewed: high-dose nicotinic acid measurably lowers LDL cholesterol and triglycerides and raises HDL, but two large randomised trials adding it to statin therapy (AIM-HIGH, HPS2-THRIVE) found no reduction in cardiovascular events and HPS2-THRIVE found more serious side effects. NICE NG238 therefore advises against using niacin to prevent cardiovascular disease; the UK pathway prefers statins, ezetimibe and PCSK9 inhibitors. This is a prescribing-tier decision, not a food-supplement use. [6,7,3]

  3. Skin-cancer prevention (nicotinamide, dermatology)

    Evidencelimited

    The research Camden reviewed: one phase-3 randomised trial (ONTRAC, NEJM 2015) reported that nicotinamide 500 mg twice daily lowered the rate of new non-melanoma skin cancers over 12 months in patients with a history of multiple skin cancers, with the benefit not persisting after stopping. This is a specialist dermatology decision for high-risk patients, not a general-population use; a later transplant-recipient trial did not replicate the benefit. [10]

Safety

Nicotinamide at typical food-supplement doses is very well tolerated. Nicotinic acid above ~50 mg produces flushing; chronic high-dose nicotinic acid (>500 mg/day) is a pharmacological-tier intervention with hepatotoxicity, glucose, and uric-acid considerations.

Talk to your pharmacist or GP first if you:

  • You have liver disease — high-dose nicotinic acid is hepatotoxic.
  • You have diabetes or impaired glucose tolerance — high-dose niacin can worsen glycaemic control.
  • You have a history of gout / hyperuricaemia — nicotinic acid raises serum urate.
  • You take statins or other lipid-modifying medication — discuss with your prescriber before adding high-dose niacin.
  • You are pregnant or breastfeeding — NRV-tier supplementation is appropriate.

Common side effects: Nicotinic acid: flushing, GI upset, headache. Nicotinamide: very well tolerated.

Pregnancy and breastfeeding

UK dietary reference values do not add a pregnancy increment for niacin (the requirement is set relative to energy intake). Niacin from a varied diet, or NRV-tier supplementation where intake is low, is appropriate. High-dose nicotinic acid: avoid. Talk to your GP, midwife or pharmacist before starting any supplement in pregnancy.

UK dietary reference values add a small breastfeeding increment for niacin (about +2 mg niacin equivalents/day). Niacin from a varied diet, or NRV-tier supplementation, is appropriate; high-dose nicotinic acid: avoid.

Talk to your GP, midwife, or pharmacist before starting any supplement during pregnancy or breastfeeding.

More clinical detail (for clinicians and informed readers)

Contraindications

  • Active liver disease (high-dose nicotinic acid).
  • Active gout (high-dose nicotinic acid).
  • Known hypersensitivity.

Drug interactions

  • Statins — additive myopathy risk at high-dose niacin; specialist supervision.
  • Anticoagulants — modest INR effect at high doses.
  • Diabetes medication — high-dose nicotinic acid can worsen glycaemic control.
  • Allopurinol / urate-lowering — high-dose nicotinic acid raises urate.

This is not an exhaustive list. Always tell your prescriber and pharmacist about every supplement you take.

Common side effects

  • Flushing (nicotinic acid only) — typically lasts 30–60 minutes, intensity reduces with continued use.
  • Mild GI symptoms.

Rare side effects

  • Hepatotoxicity — high-dose nicotinic acid (>500 mg/day chronic).
  • Hyperglycaemia / glucose dysregulation — high-dose nicotinic acid.
  • Hyperuricaemia / gout exacerbation — high-dose nicotinic acid.
  • Allergic reactions — rare.

How to take it

Typical supplemental range
NRV 16 mg/day. Common supplement doses 10–50 mg/day (typically nicotinamide). Pharmacological lipid-modifying nicotinic acid is 500–2,000 mg/day under medical supervision.
Timing
No specific timing requirement.

How to spot quality

Look for

  • Form named — nicotinamide (non-flushing) or nicotinic acid (flushing).
  • NRV percentage stated.
  • Avoid "inositol hexanicotinate" / "flush-free niacin" without clear declaration of the active form.
  • GMP-certified manufacture.

Red flags

  • Generic "vitamin B3" with no form named — for daily supplement use, nicotinamide is the safer default.
  • High-dose nicotinic acid (>50 mg) sold for general wellness rather than under medical supervision.
  • Marketing implies cardiovascular event prevention — not supported.

Where Camden lands · meets the bar

Camden Medicals does not currently sell a standalone vitamin B3 SKU. Niacin appears as an adjunct active in two multi-active B-vitamin products Camden is evaluating — a daily B-complex (18 mg NE/cap as nicotinamide, 113 % NRV — claim-eligible) and a Ginkgo B+ blend (16 mg/cap as nicotinamide, 100 % NRV). Both clear the look-for bar — both use the non-flushing nicotinamide form, both declare NRV.

Commonly combined with

Other ingredients that share a biological pathway, cofactor relationship, or evidence-backed protocol with this one. Mechanisms below cite primary physiology — not folk pairing. Doses are literature ranges, not recommendations. Talk to your pharmacist or GP before changing your stack, especially if you take prescription medication.

Niacinamide (Topical, Vitamin B3 amide form)

Limited evidence

Topical sister entry — niacinamide is the topical-skin form of vitamin B3 amide. The UK licence for nicotinamide is TOPICAL only.

Same molecule (nicotinamide / niacinamide) in a different delivery context: applied to the skin rather than swallowed. Camden's niacinamide entry covers that topical context.

Evidence: Graded on the UK BNF nicotinamide monograph, which lists exactly ONE licensed indication — inflammatory acne vulgaris, applied TO THE SKIN, twice daily. There is no by-mouth route and no oral indication anywhere in that monograph, so this row is a TOPICAL-licence statement and must not be read as licensing oral vitamin B3 for skin. [11]

Doses studied: Oral 16 mg/day NRV (the B3 nutrient reference value — a nutrition figure, NOT a licensed indication). Topical 5-10%.

NAD+ (Nicotinamide Adenine Dinucleotide)

Insufficient evidence

NAD+ precursor cluster — B3 (niacin / nicotinamide) → NAD+ via salvage pathway.

Niacinamide is the most-direct NAD+ precursor via the salvage pathway. UK Article 13.1 B3 energy-metabolism + nervous-system claims.

Evidence: Camden nad-plus + nmn NB-161 cluster.

Doses studied: 16 mg B3 + nicotinamide riboside / NMN per Camden nad-plus + nmn.

Found in Camden: Clarifera® NMN Complex 90 Delayed Release Capsules

Related ingredients

Sources

Numbered references cited above plus general authoritative reading. Citations in the body link to the matching number here.

How to read these sources:

  • Tier 1 (UK authoritative): NHS, NICE, BNF, EFSA, FSA, GB NHC Register, SACN, MHRA.
  • Tier 2 (primary literature): peer-reviewed RCTs cited by PMID.
  • Tier 3 (mechanistic): in-vitro / animal-model literature — interpret with caveat.
  1. NHS — B vitamins and folic acid
  2. GB Nutrition and Health Claims Register — Niacin claims
  3. NICE NG238 — Cardiovascular disease: risk assessment and reduction, including lipid modification
  4. BNF — Nicotinic acid
  5. British Association of Dermatologists — Nicotinamide for non-melanoma skin cancer (patient information)
  6. PubMed PMID 22085343
  7. PubMed PMID 25014686
  8. PubMed PMID 41876960
  9. PubMed PMID 34882669
  10. PubMed PMID 26488693
  11. BNF — nicotinamide

Verifera® is published by Camden Medicals — a UK supplement retailer. We have a commercial interest in some of the ingredients described here; we declare it on every page and our editorial process forbids adjusting copy to favour our own products. Read our editorial policy.

This page is information, not medical advice. Talk to your pharmacist or GP before starting any supplement, especially if you take prescribed medicines, are pregnant or breastfeeding, or have an existing condition.

Suspected side effects can be reported to the MHRA via the Yellow Card scheme: yellowcard.mhra.gov.uk