vitaminVitamin B3 (Niacin)
vitamin

Vitamin B3 (Niacin).

4.7
Reviewed by Pierson Riley — Founder, UtritionReviewed under Utrition’s editorial methodologyLast reviewed Jan 2026Allergen-free

A water-soluble vitamin with two main forms: niacin and niacinamide.

vitaminwater-solubleenergylipids
Evidence
A
Strong evidence
Best time
Morning
Food reduces flushing
Typical dose
14–500
mg
Primary use
Vitamin
Quick answer

Vitamin B3 (Niacin) in one minute. A water-soluble vitamin with two main forms: niacin and niacinamide. Typical dose: 14–500 mg. Take in the morning or afternoon with food. High-dose niacin causes temporary flushing, itching, and warmth.

What is Vitamin B3 (Niacin)?

Niacin (nicotinic acid) and niacinamide (nicotinamide) are forms of vitamin B3. Both support energy metabolism. Niacin at high doses can improve lipid profiles but causes flushing. Niacinamide does not flush or affect lipids but supports NAD+ production.

Energy metabolism
Lipid improvement (niacin)
Skin health (niacinamide topical)

Keep reading

What is Vitamin B3 (Niacin)?

A water-soluble vitamin with two main forms: niacin and niacinamide.

Niacin (nicotinic acid) and niacinamide (nicotinamide) are forms of vitamin B3. Both support energy metabolism. Niacin at high doses can improve lipid profiles but causes flushing. Niacinamide does not flush or affect lipids but supports NAD+ production.

What the evidence says

The overall evidence grade for Vitamin B3 (Niacin) is A (strong — consistent, high-quality human evidence (systematic reviews, well-powered RCTs)). Essential nutrient. High-dose niacin effects on lipids well-documented.

Specific findings with supporting evidence:

Best-supported outcomes:

Where marketing outpaces evidence:

Dose and timing

The typical effective dose for Vitamin B3 (Niacin) is 14–500 mg. Higher doses for lipids require monitoring.

Take it in the morning and afternoon with food. Food reduces flushing.

Who it's for, and who should skip it

Most relevant for:

Not appropriate for:

Safety and cautions

Caution: Niacin flush. High-dose niacin causes temporary flushing, itching, and warmth. Caution: Liver. High-dose niacin can affect liver function; monitoring recommended.

Common mistakes

Myths vs reality

A common misconception: Niacin and niacinamide do the same thing. In reality, niacin affects lipids and flushes; niacinamide does neither.

How it interacts with other compounds

Questions people ask

What causes the niacin flush? Prostaglandin release causes blood vessel dilation, warmth, and redness.

How do I reduce flushing? Take with food, start low, or use extended-release formulations.

Editorial note

This guide summarizes the published evidence on Vitamin B3 (Niacin). It is educational content, not medical advice. Confirm with your clinician if you take prescription medications or manage a chronic condition.