Does niacinamide shrink pores? What studies show

Large pores are one of the most common reasons people buy a niacinamide serum. Pores are the openings of hair follicles, and oil reaches the skin surface through them. The American Academy of Dermatology's advice is about making them less noticeable. This guide covers the one trial that measured niacinamide and pores, what the American Academy of Dermatology says makes pores look larger, and where niacinamide fits. For the full overview of the ingredient, see what niacinamide does for your skin.

Why pores look large

The American Academy of Dermatology names several reasons pores look bigger:

• Clogs. "When pores clog, they expand, which can make your pores look more noticeable."
• Oil. "Clogged pores or an oily complexion can make pores look larger."
• Irritation. Hot water and scrubbing irritate skin, and "when skin is inflamed, pores tend to be more noticeable."
• Loss of firmness. "As we age, our skin loses its firmness and starts to sag. Pores look larger when skin sags." Sun damage speeds this up.

A 2017 review of oily skin in the Journal of Clinical and Aesthetic Dermatology describes oily skin as a common concern because of "its association with larger facial pores."

Each cause has its own fix. Niacinamide may help with oil. Clogs, irritation and loss of firmness need other steps.

The niacinamide pore trial

The only trial read for this guide that measured pores with niacinamide alone was published in 2007 in the Journal of Cosmetic Dermatology.

Detail	What the trial did
People	52 adults in Taiwan, split into two groups
Group 1	4 percent niacinamide plus 0.03 percent kinetin, another skin care ingredient
Group 2	4 percent niacinamide alone
Design	Product on one side of the face, and a placebo, a look-alike product with no active ingredient, on the other, for 12 weeks; neither the people nor the researchers knew which side got what
Measured	Pores, spots, wrinkles and evenness, with instruments, at weeks 4, 8 and 12
Result for niacinamide alone	"Significant reductions in pore and evenness counts at week 8"

The trial measured pores with instruments, so the result is a measured drop in the pores the instruments could count. The summary gives no size for the drop and no rating of what people saw in the mirror. The trial was designed to test anti-aging effects, with pores as one of several measures.

A 2004 trial of 5 percent niacinamide in 50 women, run by a company that sells skin care, reported better skin texture, among other changes. Pores were outside what that trial counted.

What dermatologists agree on for large pores

In 2025, the Journal of the American Academy of Dermatology published a study that asked 62 cosmetic dermatologists at 43 centers which ingredients they recommend for common skin concerns. For large pores, the doctors agreed on retinoids. Niacinamide reached agreement for redness and dark spots, and not for large pores.

The American Academy of Dermatology's own page on pores does not mention niacinamide. It lists:

1. Non-comedogenic skin care and makeup, meaning products made so they will not clog pores.
2. Washing twice a day with a gentle cleanser and warm water.
3. A product with retinol or retinyl palmitate, applied before bed.
4. Treating acne, including a cleanser with salicylic acid.
5. Broad-spectrum sunscreen, SPF 30 or higher, every day.
6. Safe exfoliation.
7. Never scrubbing, picking or squeezing.
8. Treating sagging skin with a dermatologist.

The page adds that people who are pregnant or breastfeeding should not use a product containing retinol or retinyl palmitate.

How niacinamide might help pores

Niacinamide may help pores look smaller in two ways:

• Less oil. A 2006 trial found 2 percent niacinamide lowered facial oil in 100 Japanese adults over 4 weeks. Since oil makes pores look larger, less oil may help. The niacinamide for oily skin guide covers that trial.
• Smoother surface. A 2010 review mentions a theory that niacinamide may speed up how fast the top layer of skin renews, working as a "mild exfoliant." That is a theory, with no study linking it to pore size.

For blackheads and clogged pores, salicylic acid and retinoids are the usual choices, because unclogging pores is their main action.

A routine for pores that look large

Put the steps with the most support first, and add niacinamide as an extra:

Step	Evidence
Non-comedogenic products on your face	AAD recommendation
Gentle cleanser twice a day, warm water, no scrubbing	AAD recommendation
Sunscreen SPF 30 or higher every morning	AAD recommendation
Retinol, or a retinoid such as adapalene, at night	AAD recommendation and 2025 expert agreement
Niacinamide 2 to 5 percent, morning or night	One pore trial and one oil trial

If you also have acne, adapalene 0.1 percent treats acne and is a retinoid, so it covers both jobs. The complete acne skincare routine shows how to start it. Add one product at a time and patch test each one with how to patch test a new skincare product.

What strength, and how long

The pore trial used 4 percent. The oil trial used 2 percent. No study read for this guide tested 10 percent or higher on pores. A 2005 safety review found no irritation up to 5 percent and no stinging up to 10 percent in human tests. A strength from 2 to 5 percent matches what was tested. The niacinamide percentage guide compares each strength.

Expect slow change. The pore trial found a difference at week 8, and it ran for 12 weeks. Take a photo in the same light every 2 weeks, since slow change is hard to judge in the mirror.

Habits that make pores look larger

Some daily habits undo the benefit of any product. The American Academy of Dermatology warns against each of these:

• Hot water. "Hot water can irritate your skin, causing pores to look larger." Warm water is its advice.
• Scrubbing. "Scrubbing can irritate your skin, causing inflammation." Irritated skin shows pores more.
• Picking and squeezing. "Picking at, squeezing, or digging into your pores can also irritate your skin, making pores look more noticeable."
• Makeup and creams that clog. If a product does not say non-comedogenic, oil free or "won't clog pores," the AAD's advice is to skip it on your face.
• Skipping sunscreen. "The more sun damaged your skin, the less firmness it has," and pores look more noticeable as firmness drops.

These cost nothing, and they address causes that niacinamide leaves untouched.

How to use niacinamide for pores, step by step

1. Wash with a gentle cleanser and warm water.
2. Apply a thin layer of a 2 to 5 percent niacinamide serum or moisturizer to the whole face. Pores are everywhere, so a thin, even layer beats dabs on the nose.
3. Moisturize if your niacinamide product is a serum. Choose a light, non-comedogenic moisturizer.
4. Add sunscreen in the morning, SPF 30 or higher.
5. Repeat once or twice a day. The pore trial ran 12 weeks, so plan for at least 8.

If you use a retinol or retinoid at night, niacinamide can go on in the morning, which keeps the two apart while you see how your skin reacts. The how to use a niacinamide serum guide covers timing in more detail.

What the pore trial did not answer

One trial leaves open questions. Its summary gives no results for people with acne or by skin type, and it followed people for 12 weeks only. It tested 4 percent, while many serums today sell 10 percent or more. It was run in one country. Until more studies exist, the fair summary is that niacinamide lowered measured pore counts once, in one group of adults.

Why results can disappoint

Many people try a niacinamide serum for pores and see little change. Common reasons:

• Age and sun damage are the main cause. The pore trial measured pores, spots, wrinkles and evenness, and firmness was outside that list. The AAD points to sunscreen, retinol and in-office treatments for sagging skin.
• Pores are clogged. A clogged pore needs salicylic acid or a retinoid more than niacinamide.
• The time was too short. Two weeks is too early to judge.
• Expectations were too high. A measured drop in pore counts may be small to the eye.

When to see a dermatologist

See a dermatologist if pores come with painful acne, if you have many blackheads that do not improve after 12 weeks of steady care, or if you want in-office treatment for sagging skin. A dermatologist can also exfoliate the skin safely during an office visit, which the AAD describes as one option for pores.