Niacinamide: How Can One Ingredient Help with Uneven Tone, Moisture, and So Much More?

By Daebbang

“Niacinamide is in my brightening serum, my moisturizer, and even products that promise less shine. Can it really help in so many ways? If so, should I choose 10% or 20% instead of 5%?”

Niacinamide is a form of vitamin B3 connected to several skin functions. Human studies have looked at not only skin tone, but also moisture, the skin barrier, sebum, and fine lines. Still, it is not an ingredient that solves every concern equally well in a single product.

I recommend starting by deciding what you most want to improve: dryness, dark spots, or shine. Once you understand the reasons, it becomes easier to choose a product without focusing only on the percentage.

What is niacinamide, and why does it have so many roles?

Niacinamide is a form of vitamin B3 and is the same ingredient as nicotinamide. It is not a particular company’s brand name.

Our cells use niacinamide to make helper molecules in the NAD and NADP families. These molecules participate in producing energy, making needed fats, and responding to damage. [US NIH vitamin B3 fact sheet]

Think of a skin cell as a small workshop. The workshop produces energy, makes the materials it needs, and maintains damaged areas. Niacinamide is a material used to make helper molecules involved in several of these jobs.

This provides a common background for understanding the range of possible effects. However, it has not been established that brighter-looking skin, better moisture, and less sebum all result from a single pathway of increased NAD. Research on skin-barrier components, inflammatory signals, and pigment transfer needs to be considered separately.

How can it help dry skin?

It may help build the skin’s outer protective layer, so less water escapes.

Imagine the outermost skin layer as a brick wall. Skin cells are the bricks, and fats such as ceramides fill the spaces between them. In cell experiments, niacinamide increased the activity of enzymes involved in making these fats. Research applying it to dry skin also found increases in barrier lipids and reduced water loss. [Tanno et al., 2000]

In a study of dry forearm skin in 28 people with atopic dermatitis, a 2% cream used for 4–8 weeks increased skin hydration and reduced water loss. This was a study of the moisturizing effect of a particular cream. It does not mean that every 2% serum has the same effect or that it can replace treatment for atopic dermatitis. [Soma et al., 2005]

If dryness is your main concern, look first at whether the moisturizer as a whole keeps your skin comfortable, rather than only checking the percentage of niacinamide.

How can it support moisture and reduce oil? Isn’t that a contradiction?

The fats that fill the skin barrier are different from the sebum that makes the surface shiny. Barrier lipids sit between the outer skin cells, while sebum comes from sebaceous glands. Grouping them all together as “oil in the skin” makes it easy to confuse their roles.

There are human sebum studies using 2% products, too. In a trial involving 100 Japanese participants, the group using a 2% moisturizer had a lower sebum excretion rate at 2 and 4 weeks. In a separate trial involving 30 White participants, the amount of sebum on the surface decreased after 6 weeks, but the decrease in the rate of sebum output was not clear. [Draelos et al., 2006]

It is therefore reasonable to say that niacinamide may help manage shine. The detailed mechanism is not yet clear, however, and these studies alone do not show that it shrinks sebaceous glands or pores themselves.

How might it help acne?

Effects on inflammatory signals have been studied, as well as effects on sebum. In skin cells stimulated with acne-associated bacteria, niacinamide reduced the production of IL-8, a signal that recruits inflammatory cells. Put simply, the experiment observed a reduction in a signal that can amplify inflammation. [Grange et al., 2009]

A small human trial of 4% nicotinamide gel for 8 weeks also observed improvement in inflammatory acne. Although 76 people enrolled, only 49 were included in the efficacy evaluation. The finding of no clear difference from the antibiotic used for comparison cannot be interpreted as proof of equivalent treatment effects. [Shalita et al., 1995]

I recommend viewing it as an ingredient for supporting the care of acne-prone skin. If large, painful pimples keep returning or scars are developing, prioritize acne treatment instead of waiting while increasing the concentration of a cosmetic product.

What does it do to pigment when it helps brighten skin?

One of its best-studied actions is reducing the transfer of tiny pigment-containing packets to surrounding skin cells. [Hakozaki et al., 2002]

Skin contains a pigment called melanin. The cells that make it, melanocytes, sit near the bottom of the epidermis and pass pigment to neighboring skin cells through branching arms. The tiny packets carrying that pigment are called melanosomes.

Think of a delivery service: melanin is the contents, and the melanosome is the shipping box. In cell experiments, niacinamide reduced the transfer of these boxes to neighboring cells. [Hakozaki et al., 2002]

Human studies have also observed improvements in melasma and facial pigmented spots. For example, an 8-week trial of a 4% cream in 27 women with melasma observed pigment improvement while sunscreen was also used. This should not be extended to mean that all moles or age spots will disappear. [Navarrete-Solís et al., 2011]

Can it also help fine lines and skin texture?

A human study of a 5% product observed improvements in fine lines and skin texture. Fifty White women used a 5% moisturizer on one side of the face and the same moisturizer without niacinamide on the other for 12 weeks. Fine lines, texture, pigmented spots, and red blotchiness improved; a related report also described improvement in instrument-measured elasticity. [Bissett et al., 2004] [Bissett et al., 2005]

This research was supported by a cosmetics company and carried out by company researchers. Its findings also need to be understood in the context of the specific product and participants. Do not interpret it as the effect of a procedure that substantially improves deep wrinkles or facial sagging, or as a treatment for every type of facial redness.

Several effects may contribute to these changes, including support for the skin barrier, moisture, and responses to cellular stress. Experiments in cultured skin cells and skin tissue outside the body have also found reduced ultraviolet-related energy loss or support for the repair of damaged DNA. These experiments do not fully explain the cause of actual fine-line improvement, and they do not mean that an ordinary serum replaces sunscreen. [Park et al., 2010] [Surjana et al., 2013]

If it has so many roles, wouldn’t a higher concentration be better?

A variety of mechanisms does not, by itself, establish that 10% or 20% is better. Being a material that cells use does not mean that applying more improves every function in proportion.

The 2% moisture and sebum studies, the 4% melasma study, and the 5% fine-line study discussed above involved different participants, products, and outcomes. Their percentages cannot be lined up to make an effectiveness ranking.

There are also clinical trials of products containing 10%. A study following 50 women with melasma for 60 days used a product that also contained a vitamin C derivative and hyaluronic acid. Its results therefore cannot be isolated as the effect of 10% niacinamide alone or used to show superiority over 5%. [Barbosa et al., 2024]

Conversely, a product cannot be declared irritating simply because it contains 10%. A safety assessment includes sting-testing findings in which no stinging was observed at concentrations up to 10%. Ultimately, consider the complete formulation, the benefits you see on your own skin, and any discomfort, alongside the concentration. [CIR safety assessment, 2005]

So, which product should I start with?

If dryness bothers you most

Start with a moisturizer you can use comfortably. Niacinamide is one ingredient worth considering when choosing a moisturizer. Before adding a high-concentration serum, check whether tightness after washing and dryness are already well controlled. You may also find Why Does My Skin Still Feel Tight After Moisturizer? helpful.

If dark spots and uneven tone are your main concerns

I recommend one 4–5% product as a starting point. This suggestion draws on human studies that observed pigment improvement with products in this range. It is not an optimal concentration that applies to every possible benefit. [Navarrete-Solís et al., 2011] [Bissett et al., 2004]

Use sunscreen as well, and reassess your skin tone and how the product feels after about 8–12 weeks. This is a practical guide based on the observation periods in the studies. Photos taken in the same lighting can make comparison easier. If the change is limited, I recommend checking sun protection and the type of pigmentation before immediately increasing the concentration.

If shine or acne is the concern

Judge by whether shine actually decreases and your skin feels comfortable. Studies have used 2% products, so there is no reason to automatically choose a high concentration. If inflammatory acne keeps recurring or scars are developing, keep niacinamide as supportive skincare and prioritize treatment.

If you are already doing well with a 10% product

Keep using it if it helps and causes no discomfort. You do not need to switch to 5% because of this article. Nor is the number alone a sufficient reason to replace a well-suited 5% product with 20%.

Add only one new product at a time. If stinging, redness, or itching is persistent or severe, stop rather than putting up with it as a sign that the product is working. If it continues after stopping or the reaction is severe, have it assessed medically.

On an oozing or raw treatment site, follow the wound-care instructions you were given before trying a new ordinary serum. Helping the barrier of intact skin is different from being suitable for an open wound. [Goodman et al., 2025]

Start with a moisturizer for dryness, consider 4–5% as a starting point for dark spots, and prioritize treatment for recurring or scarring acne. Keep a product that suits your skin and helps. Choose niacinamide for your main skin concern rather than for the highest number.