Niacinamide
Vitamin B3 for your skin — reduces pores, fades pigmentation, strengthens your barrier. One of the most versatile and well-tolerated skincare actives you can use.
Niacinamide is a form of vitamin B3 that helps your skin in multiple ways — it tightens pores, fades dark spots, reduces oil, and strengthens your skin barrier. You can use it topically (serum) or take it as a supplement for NAD+ support.
Good for you if: You have oily or combination skin, enlarged pores, post-acne dark marks, uneven skin tone, or want a gentle active that plays well with everything else in your routine.
Dive deeper into the researchCommon side effects
- Mild flushing or redness at concentrations above 5% (topical)
- Slight tingling when first starting — usually resolves in a few days
- Oral doses above 1 g/day may cause nausea or flushing
What does niacinamide do?
Your skin needs ceramides (fats) to hold moisture and keep irritants out. Niacinamide boosts your skin's own production of these ceramides, which is why it strengthens your barrier so effectively.
It also reduces melanin transfer to your skin cells — that's why dark spots and uneven tone start fading. And it regulates sebum production, so your skin gets less oily without drying out.
What can you expect?
- Smaller-looking pores — the most noticeable change, usually within 4–6 weeks
- Less oiliness — sebum production drops without stripping your skin
- Fading dark spots — post-acne marks and sun damage lighten over 8–12 weeks
- Stronger barrier — less sensitivity, less redness, skin feels more resilient
- Better texture — smoother, more even-toned skin overall
How to use it
Topical: Apply a 5% niacinamide serum morning and evening — after cleansing, before moisturiser. It layers well with almost everything.
Oral: 500 mg/day as nicotinamide for NAD+ and systemic skin support. Take with food.
Best combinations: Niacinamide pairs well with vitamin C, retinol, hyaluronic acid, and alpha arbutin. It actually helps buffer the irritation from stronger actives like retinoids.
What to avoid: Don't use with copper peptides in the same step — niacinamide can bind to copper ions. Space them by a few hours if you use both.
Topical vs oral — which do you need?
| Topical (5% serum) | Oral (500 mg) | |
|---|---|---|
| Best for | Pores, oil, pigmentation | NAD+ support, skin cancer prevention |
| How fast | 4–8 weeks | 8–12 weeks for skin effects |
| Evidence | Strong (20+ studies) | Good (systemic + ONTRAC trial) |
| Cost | ₹200–600 for a good serum | ₹300–500/month |
For most people, topical 5% is the best starting point. Add oral if you want the NAD+ and cellular benefits too.
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Get early accessFrequently Asked Questions
Can I use niacinamide with vitamin C?
Yes. The old myth that niacinamide and vitamin C cancel each other out has been debunked. They work at different stages of the pigmentation pathway and actually complement each other well. You can layer them in the same routine without issues.
What percentage of niacinamide is best?
5% is the sweet spot for most people — well-studied and effective without irritation. 10% works for oilier skin or stubborn pigmentation but can cause flushing in sensitive skin. Going above 10% doesn't add benefit and increases irritation risk.
Does niacinamide help with acne scars?
It helps fade post-inflammatory hyperpigmentation (the dark marks acne leaves behind) by reducing melanin transfer to skin cells. For actual textured scars (pitting, rolling), you'll need treatments like retinoids, microneedling, or laser — niacinamide won't fix those.
Should I take niacinamide orally or use it topically?
For skin benefits like pore size, oil control, and pigmentation, topical 5% is more direct and better studied. Oral niacinamide (500 mg/day) supports NAD+ levels and has systemic benefits including skin cancer prevention. Many people do both.
How it works in your body
Niacinamide is converted to NAD+ in your cells — the coenzyme that powers hundreds of metabolic reactions. In skin specifically, it boosts ceramide and fatty acid synthesis in the stratum corneum, which strengthens your barrier.
For pigmentation, it doesn't inhibit melanin production directly (unlike kojic acid or arbutin). Instead, it blocks the transfer of melanosomes from melanocytes to keratinocytes — your skin cells still make pigment, but less of it reaches the surface.
What the studies show
- Pore size: 5% niacinamide reduced pore area by ~20% after 8 weeks in a Japanese split-face RCT
- Pigmentation: Significant reduction in hyperpigmented spots vs vehicle after 8 weeks (Hakozaki et al.)
- Sebum: 2% niacinamide reduced sebum excretion rate by ~23% after 4 weeks
- Barrier: Increased ceramide levels and reduced transepidermal water loss in multiple trials
- Skin cancer: Oral 500 mg twice daily reduced new non-melanoma skin cancers by 23% (ONTRAC trial)
Side effects & safety
Niacinamide is one of the most well-tolerated actives in skincare. Issues are uncommon but here's what to know:
- Flushing — Topical concentrations above 5% can cause temporary redness, especially in sensitive skin. If this happens, drop to 4–5% and build up.
- Tingling — Some people feel a mild tingle when first applying. This usually resolves within a week of consistent use.
- Niacin flush (oral) — This happens with niacin (nicotinic acid), not niacinamide. But very high oral doses (2+ g/day) of niacinamide can still cause GI discomfort.
- Breakouts — Rarely reported. More likely related to other ingredients in the serum formula rather than niacinamide itself.
Who should be careful: If you have very reactive or rosacea-prone skin, patch test first and start with a lower concentration (2–4%).
Which labs to check
If you're taking oral niacinamide for NAD+ support, these markers help track your response:
- NAD+ levels — available through specialty labs, shows direct impact
- Liver enzymes (ALT, AST) — monitor if taking high-dose oral niacinamide long-term
- Fasting glucose & HbA1c — high-dose niacin forms can affect insulin sensitivity
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