Vitamin B3 (Niacin)

Essential B vitamin crucial for energy metabolism, cholesterol regulation, and cellular repair

Scientific nameNicotinic Acid FormulaC6H5NO2 Molecular weight123.11 g/mol CAS59-67-6

90 absorption score

6 safety / 10

8 USD per month

5 documented interactions

Check it against something

Evidence level B

Vitamin B3 (Niacin) with:

78 out of 100

Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Cholesterol improvement

Raises HDL by 20-35% and lowers LDL by 10-25%

Inhibits VLDL synthesis and promotes HDL formation Evidence A-grade 4-8 weeks

Energy metabolism support

Essential component of NAD+ and NADP+ coenzymes

Required for glycolysis, Krebs cycle, and electron transport Evidence A-grade 1-2 weeks

DNA repair and longevity

Supports cellular repair and anti-aging pathways

Substrate for poly(ADP-ribose) polymerase enzymes Evidence B-grade 4-12 weeks

Brain function support

May improve cognitive function and memory

Required for neurotransmitter synthesis and brain energy Evidence B-grade 4-8 weeks

Skin health

Supports healthy skin and may reduce inflammation

Anti-inflammatory effects and improved circulation Evidence B-grade 2-6 weeks

Others take these for the same thing

Same goal, different mechanism — check any of them against this one

Ashwagandha Stress management & energy 300-600mg A 75% Vitamin B12 (Cyanocobalamin) Energy & nerve support 250-1000 mcg A 70% Coenzyme Q10 (CoQ10) Heart health & cellular energy 100-200mg A 10% Fish Oil (EPA/DHA) Heart & brain health 1-2g EPA/DHA A 85% Phosphorus Bone health & energy metabolism 700-1250mg A 80% Vitamin B3 (Niacinamide) Energy & skin health (no flush) 100-1000 mg A 88%

Every pair we checked

12 combinations scored by the engine

Vitamin B3 (Niacin) + Caffeine No documented interaction either way No known interaction 70

Vitamin B3 (Niacin) + Creatine Monohydrate No documented interaction either way No known interaction 70

Vitamin B3 (Niacin) + Whey Protein No documented interaction either way No known interaction 70

Vitamin B3 (Niacin) + Turmeric No documented interaction either way No known interaction 70

Vitamin B3 (Niacin) + Chromium GTF Both improve glucose and lipid metabolism Works better together 78

Vitamin B3 (Niacin) + Vitamin D3 Prevents arterial calcification from vitamin D Works better together 78

Vitamin B3 (Niacin) + Lactase Improved calcium absorption when consuming dairy Works better together 82

Vitamin B3 (Niacin) + Bovine Collagen Essential for collagen synthesis and cross-linking Works better together 82

Vitamin B3 (Niacin) + DHA Prevents oxidation of DHA and enhances stability Works better together 82

Vitamin B3 (Niacin) + Coenzyme Q10 (CoQ10) Both support mitochondrial energy production Works better together 87

Vitamin B3 (Niacin) + Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula Synergistic cardiovascular benefits Works better together 90

Vitamin B3 (Niacin) + Calcium Carbonate Essential for calcium absorption and utilization Works better together 94

Dosage

With food to reduce flush

Daily50-500 mg

Maintenance50-200 mg

Therapeutic500-2000 mg

Cholesterol therapy1000-3000 mg (medical supervision)

Maximum35 mg (without medical supervision)

Upper limit 35 mg NIH ODS

Before you take it

VeganYes

When to expect it

First Effects30-60 minutes for flush, 1-2 weeks for energy

Peak Benefits6-12 weeks for cholesterol improvements

Deficiency Development6-8 weeks with inadequate intake

Toxicity OnsetWeeks to months at high doses

How to measure it

$30-50

MarkerLipid panel (HDL, LDL, triglycerides)

OptimalHDL >40 mg/dL men, >50 mg/dL women

FrequencyEvery 6-12 weeks when using for cholesterol

What people actually reported to the FDA

CAERS, 35 reports naming it as the suspect

Most reported effects

Erythema 13

Flushing 12

Pruritus 10

Dizziness 10

Dyspnoea 9

Named as the suspect 35 reports of 52 that mention it at all

Serious outcome 82% hospitalisation, emergency room or worse

Other Serious or Important Medical Event26

Visited Emergency Room15

Life Threatening8

Reports are voluntary and unverified — they record what someone experienced while taking something, not what the compound caused. Counts skew towards products people take a lot of, and a serious outcome is more likely to be reported than a mild one, so these are not rates. How we filter them →

What actually reaches you

The label counts the carrier, your body does not

Absorption Very high 90 of 100 · best absorbed form of this compound

Delivered daily 247.5 mg

Cost per 100 mg delivered $0.11 comparative — uses the absorption score, not a measured percentage

Works better with

3 documented

Chromium

Both improve glucose and lipid metabolism

Complementary effects on insulin sensitivity · level B

Omega 3 Fatty Acids

Synergistic cardiovascular benefits

Complementary lipid-lowering mechanisms · level B

Coq10

Both support mitochondrial energy production

Complementary roles in electron transport · level C

What not to take with Vitamin B3 (Niacin)

2 documented

Alcohol

Increases niacin requirements and liver stress

Competes for NAD+ and increases metabolism · moderate significance

Isoniazid

Interferes with niacin metabolism

Depletes vitamin B6 needed for niacin synthesis · moderate significance

Medication interactions

Discuss these with a pharmacist before combining

statins Moderate

Increased risk of muscle problems when combined

What to do: Monitor CK levels, start low doses

diabetes-medications Moderate

May worsen blood glucose control

What to do: Monitor blood glucose closely

blood-pressure-medications Minor

May enhance hypotensive effects

What to do: Monitor blood pressure

Available forms

bioavailability compared

Immediate-Release Niacin 90

Extended-Release Niacin 85

Niacinamide 85

Inositol Hexanicotinate 70

Immediate-Release Niacin: Most effective for cholesterol, Least expensive, Most research

Extended-Release Niacin: Reduced flushing, Once daily dosing, Better tolerance

Niacinamide: No flushing, Good safety profile, Multiple benefits

Inositol Hexanicotinate: Minimal flushing, Slow release, Good tolerance

Food sources

before you supplement

Tuna 18.8 mg/100g · 85

Chicken breast 14.8 mg/100g · 80

Peanuts 12.0 mg/100g · 70

Mushrooms 3.6 mg/100g · 75

Enriched bread 5.0 mg/100g · 80

Too little

deficiency signs

Pellagra: dermatitis, diarrhea, dementia, death
Fatigue and weakness
Depression and irritability
Poor memory and confusion
Digestive problems
Skin lesions and photosensitivity
Rough, darkened skin

Too much

toxicity signs

Severe flushing and burning sensation
Liver toxicity and elevated enzymes
Nausea and vomiting
Glucose intolerance
Peptic ulcers (rare)
Gout attacks (increased uric acid)
Irregular heartbeat (rare)

Who benefits most

high-cholesterol

Niacin effectively improves cholesterol profile

500-2000 mg daily (with medical supervision)

cardiovascular-risk

Raises HDL and may reduce heart disease risk

100-500 mg daily

athletes

Increased energy metabolism demands

50-200 mg daily

anti-aging-focused

NAD+ precursor supports cellular repair

100-500 mg daily

mental-health

Historical use for depression and anxiety

500-1500 mg daily (with supervision)

Where to buy it

compare forms first

Look for Vitamin B3 (Niacin) at 50-500 mg per serving. The form that matters here is Immediate-Release Niacin.

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What else affects it

Beyond other supplements

Alcohol

Increases niacin requirements and liver stress

Competes for NAD+ and increases metabolism

How it works

Precursor to NAD+ and NADP+ coenzymes
Essential for glycolysis and Krebs cycle
Inhibits VLDL cholesterol synthesis
Activates GPR109A receptor (anti-inflammatory)
Substrate for poly(ADP-ribose) polymerase (DNA repair)
Required for fatty acid synthesis and breakdown

Key findings

what the evidence supports

Raises HDL cholesterol by 20-35% (multiple RCTs)
Reduces cardiovascular events in combination therapy (AIM-HIGH trial)
Essential for preventing pellagra (historical evidence)
NAD+ precursor supports cellular longevity pathways (emerging research)

Sources: NIH Examine.com · data reviewed 2026-08-02

Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →

Common questions

What are the benefits of Vitamin B3 (Niacin)?

Documented effects: Cholesterol improvement; Energy metabolism support; DNA repair and longevity; Brain function support. Raises HDL by 20-35% and lowers LDL by 10-25%

How much Vitamin B3 (Niacin) should you take per day?

The common daily range is 50-500 mg. By goal — maintenance: 50-200 mg; therapeutic: 500-2000 mg; cholesterol therapy: 1000-3000 mg (medical supervision); maximum: 35 mg (without medical supervision).

When is the best time to take Vitamin B3 (Niacin)?

With food to reduce flush. First effects are typically reported within 30-60 minutes for flush, 1-2 weeks for energy.

What are the side effects of Vitamin B3 (Niacin)?

At excessive doses: Severe flushing and burning sensation, Liver toxicity and elevated enzymes, Nausea and vomiting, Glucose intolerance, Peptic ulcers (rare). Safety rating at normal doses is 6 out of 10.

What should you not take with Vitamin B3 (Niacin)?

Separate it from Alcohol, Isoniazid by two to four hours. Increases niacin requirements and liver stress

Does Vitamin B3 (Niacin) interact with medications?

Documented interactions with statins, diabetes-medications, blood-pressure-medications. Discuss these with a pharmacist before combining.

How much Vitamin B3 (Niacin) is too much?

The tolerable upper intake level is 35 mg per day for adults, per NIH ODS. Above that, the risk of adverse effects rises: Severe flushing and burning sensation, Liver toxicity and elevated enzymes, Nausea and vomiting.

How do you know if you need Vitamin B3 (Niacin)?

The marker is Lipid panel (HDL, LDL, triglycerides), optimal range HDL >40 mg/dL men, >50 mg/dL women. Common deficiency signs: Pellagra: dermatitis, diarrhea, dementia, death, Fatigue and weakness, Depression and irritability, Poor memory and confusion.

Taken for

62 Energy & Metabolism

Vitamin B12 (Methylcobalamin) · Ashwagandha · Vitamin B12 (Cyanocobalamin)

52 Heart

Fish Oil (EPA/DHA) · EPA · Olive Oil Extract