Niacinamide: What It Does and When to Use It

In short

🔑 It was measured at 5%, and that is where improvement in expression lines, pigmentation and texture was demonstrated in 12-week half-face trials. A bottle saying “niacinamide” without a concentration does not say much.
The best-documented part is the pigment: it reduces the transfer of melanosomes from the melanocyte to the keratinocyte — that is, it steps in before the mark becomes visible.
It is the active for skin that tolerates no others. When vitamin C stings or reddens, niacinamide does a similar job without that cost.
⚠️ It is not a powerful depigmenting agent and it does not replace a retinoid. It works slowly and shows over months, like everything that works in skincare.
⚠️ The myth that “it cannot be mixed with vitamin C” does not hold up in today’s cosmetic formulations; what is true is that putting them together does not multiply the effect.
🚨 If your skin reddens daily, stings with everything or has persistent redness, that is not a choice of active: it is a reason for a consultation.

Niacinamide is the most tolerant active there is with reasonable evidence behind it. It irritates almost nobody, gets on well with everything else, does not force a change in the order of the routine and has trials measuring three different things: expression lines, pigmentation and barrier quality. It is not a spectacular active; it is one that almost never goes wrong.

And it has a specific role in our routines: when skin is too reactive for a vitamin C, the antioxidant that goes in is niacinamide. That is a rule of the tool, set by the surgeons who sign it, and it is the main reason for this page.

This page sits inside the dermocosmetics guide, where the framework of what a cosmetic can claim is set out. If you are looking for the other side of the comparison, vitamin C has a page of its own: what vitamin C does and what is wrongly attributed to it.

What it is and what it does

Niacinamide is a form of vitamin B3. In the skin it behaves as a precursor of molecules involved in cell metabolism, and from there come the effects that have been measured. What matters is not the mechanism, which takes a while to explain, but what was measured, in whom and at what concentration.

1. Pigment

The reference paper is from 2002 and studied exactly how it interferes with the formation of a mark: niacinamide inhibited between 35% and 68% of the transfer of melanosomes — the packets of pigment — from the melanocyte to the cells of the epidermis. It does not bleach, it does not destroy pigment already formed: it slows the distribution.

That explains two things you see in practice: that it works better preventing than correcting, and that it needs months to show.

2. Lines, pigmentation and texture

The half-face trials — half with product, half with vehicle, on the same person — with 5% niacinamide for 12 weeks showed improvement in expression lines, in pigmented marks and in texture. It is the study that sets the reference concentration, and that is why the first question with a bottle in hand is what percentage it contains.

3. Barrier

It is the most-cited effect and the one most noticeable on the face: the skin copes better with everything else. It is also what explains why niacinamide appears in so many moisturisers for sensitive skin.

The best-documented part is not the most advertised: it is that it steps in before the mark becomes visible.

When we choose it instead of vitamin C

Here is the house criterion, and it is a written rule of the engine that builds our routines:

Skin with a tendency to be sensitive: vitamin C can be used, choosing the formulation. The options we prioritise are the least aggressive ones.
Very sensitive skin, or sensitive with redness: no vitamin C. The antioxidant becomes niacinamide, and a moisturiser containing niacinamide scores higher than one that does not.

The reason is not that vitamin C is bad: it is that to penetrate it has to be formulated at a pH below 3.5, and that pH is exactly what reactive skin will not forgive. Niacinamide works at neutral pH, and that makes it compatible with skin that is already at its limit.

And there is an important nuance worth saying out loud: sensitive skin is a syndrome, not a skin type. The consensus document of the international group that defined it describes it as unpleasant sensations — stinging, burning, pain, itching, tingling — in response to stimuli that do not normally provoke them. It can accompany any skin, and that is why our tool asks about it separately.

The decision is not which active is better, but which one your skin can take every day.

How it is used

When: in the morning, after cleansing and before the moisturiser, if it comes as a serum. If it is inside the moisturiser, there is no extra step to add.
What it gets on with: everything. It is the easiest active in a routine to fit in.
With a retinoid: they can be used the same day, and in fact several of our retinol formulations contain niacinamide precisely to improve tolerance.
How long it takes: the trials measure at 12 weeks. Before two months there is nothing to judge.

The myth that it cannot be mixed with vitamin C

It has been going round for years and comes from an old experiment: under laboratory conditions, with heat and at high concentrations, niacinamide and ascorbic acid can react and form nicotinic acid, which causes redness. In a modern cosmetic formulation, at room temperature and with the pH controlled, that is not what happens.

What is reasonable: using them together does not automatically add up their effects, and if your skin is at the edge of its tolerance, putting two actives on at once is the quickest way to end up having to give both up. Our routine proposes one antioxidant in the morning, not two.

What it does not do

It is not a first-line depigmenting agent. On an established mark, niacinamide accompanies; it is not what removes it.
It does not replace a retinoid for wrinkles and texture: the retinol trials measure larger effects.
It does not replace sun protection. Nothing does.
It does not treat acne, rosacea or melasma. A cosmetic, by legal definition, does not treat disease. When the problem is one of those, niacinamide can be part of the supporting routine, but the treatment is decided in the consulting room.

Where it is in our shop

There is no need to buy a specific serum: in several of our products niacinamide is already inside the moisturiser or the treatment itself, which is the most convenient way to have it. Among others it is in AllSkin Med’s Barrier Defence Emulsion, Rosadermic, the Mattifying Gel Cream for combination and oily skin, and SkinCeuticals’ Advance Brightening UV Defense, which is also the sunscreen we prioritise in almost every routine.

Which one is right for you depends on your skin and on your priority, and that is exactly what the skincare routine tool resolves.

Frequently asked questions

What concentration of niacinamide should I look for?

The one that was tested is 5%. Above that there is no more evidence of efficacy and there is more chance of redness on reactive skin. If the pack does not state the percentage, you do not know: the ingredients list only requires the order to be declared, not the amount.

Does it work for pigmentation?

It helps, above all by preventing: it reduces the transfer of pigment from the melanocyte to the skin. On an already established mark, it is an accompaniment, not the main treatment. And without daily sun protection it does not deliver: that holds for any depigmenting agent.

Can I use it with retinol?

Yes, and it is one of the most reasonable combinations there is: several retinol formulations contain niacinamide to improve tolerance. What is not a good idea is starting both in the same week.

Is niacinamide or vitamin C better?

They do not compete at the same thing. Vitamin C is an antioxidant with more mileage in photoprotection and radiance, and niacinamide is more tolerant and works better on the barrier and on pigment. On very sensitive skin, the choice is clear: niacinamide.

Can it irritate?

It is rare, and it usually happens with high concentrations or on very reactive skin: transient redness on applying it. If it happens, you lower the concentration or switch to a formulation where it goes inside the moisturiser.

Can it be used while pregnant?

It is not on the list of things withdrawn during pregnancy. It is one of the reasonable options when the retinoid is set aside, and we deal with it in skincare in pregnancy and breastfeeding.

How long before it shows?

The trials measure at 12 weeks. In practice, the improvement in skin comfort is noticed sooner; the pigment and the lines need months.

Sources

Hakozaki T, Minwalla L, Zhuang J, et al. The effect of niacinamide on reducing cutaneous pigmentation and suppression of melanosome transfer. British Journal of Dermatology, 2002;147(1):20-31. PMID 12100180. — Niacinamide inhibited between 35% and 68% of melanosome transfer from the melanocyte to the keratinocyte, with no effect on tyrosinase activity or on melanin synthesis. It is the work that explains why it prevents better than it corrects.
Bissett DL, Oblong JE, Berge CA. Niacinamide: A B vitamin that improves aging facial skin appearance. Dermatologic Surgery, 2005;31(7 Pt 2):860-865. PMID 16029679. — Half-face trials with 5% niacinamide for 12 weeks: improvement in expression lines, pigmented marks and texture against the vehicle. It is the reference that sets the concentration and the timescale.
Misery L, Ständer S, Szepietowski JC, et al. Definition of Sensitive Skin: An Expert Position Paper from the Special Interest Group on Sensitive Skin of the International Forum for the Study of Itch. Acta Dermato-Venereologica, 2017;97(1):4-6. PMID 26939643. — Sensitive skin is defined as a syndrome: unpleasant sensations in response to stimuli that do not normally provoke them. It is neither a skin type nor a diagnosis, and that is why it is asked about separately before choosing an antioxidant.
Pinnell SR, Yang H, Omar M, et al. Topical L-ascorbic acid: percutaneous absorption studies. Dermatologic Surgery, 2001;27(2):137-142. PMID 11207686. — L-ascorbic acid only penetrates when formulated at a pH below 3.5. It is the figure that explains why reactive skin tolerates an effective vitamin C badly and why niacinamide, which works at neutral pH, is its alternative.
Regulation (EC) No 1223/2009 of the European Parliament and of the Council on cosmetic products. Consolidated text on EUR-Lex. — Article 19.1(g): the ingredients list is declared in decreasing order of weight above 1%, but not the concentration. It is the reason a pack that does not say “5%” gives you no way of knowing what you have.

Book your consultation

If you do not know whether your skin calls for vitamin C or niacinamide, the skincare routine tool decides with eight questions and gives you the full routine in two budgets. And if you have questions or want to fine-tune it, write to us: the medical team will go through it with you, free and with no obligation.