Does niacinamide reduce facial oil and shine?

A small 2% niacinamide trial found a population- and measurement-specific sebum signal, but that does not prove every niacinamide serum reduces visible shine or oil production.

Niacinamide for an Oily, Shiny Face: The 2% Study Has Limits

This answer uses published research and official guidance. Every source is linked. Our reviews cover products we have used.

Evidence: mixed The sources are limited, indirect, inconsistent, or specific to one formula.

Niacinamide is often sold as an oil-control switch. The most directly relevant human study is more interesting than that: one arm improved on a Sebumeter, while another did not reproduce the same endpoint.

The evidence is mixed. A 2006 study found lower Sebumeter-measured sebum excretion with a 2% niacinamide gel in its Japanese arm. Its US split-face arm found a lower casual sebum level after six weeks, but not a significant sebum-excretion difference versus untreated skin (Draelos, Matsubara & Smiles, 2006).

That supports a narrow possibility of less measurable surface oil in a similar formula (Draelos, Matsubara & Smiles, 2006). It does not guarantee a matte finish, smaller-looking pores or a treatment result.

What the 2% trial actually measured

The Japanese study enrolled 100 healthy women; 98 completed. Fifty used a 2% niacinamide hydrophilic gel and 50 used a placebo twice daily for four weeks. Sebumeter and Sebutape readings were taken at baseline, week 2 and week 4 (Draelos, Matsubara & Smiles, 2006).

The US study enrolled 30 women in a randomized split-face design for six weeks. Casual sebum level fell on the treated side at week 6, but the sebum-excretion-rate result was not significantly different from the untreated side. The authors note that increased attention to cleansing may have lowered both sides (Draelos, Matsubara & Smiles, 2006).

The important limitation is the disagreement inside one paper: the same nominal concentration did not produce the same endpoint across populations and designs (Draelos, Matsubara & Smiles, 2006).

The formula matters

The tested gel contained 2% niacinamide plus 1% panthenol. A 10% serum is not the studied formula, and a moisturizer, sunscreen or exfoliating serum can change feel, shine and tolerance even when niacinamide is present (Draelos, Matsubara & Smiles, 2006).

A separate randomized proof-of-concept study evaluated a multi-ingredient biomimetic moisturizer in oily, blemish-prone women and used a 4% niacinamide gel cream as a positive-control regimen. That is formulation evidence, not a dose-response experiment of pure niacinamide. Crossref metadata lists GlaxoSmithKline as the funder, another reason not to treat this as independent ingredient evidence (Santos-Caetano et al., 2020; Crossref metadata).

Sebum is not the same as visible shine

Sebumeter output, casual surface sebum, sebum excretion after cleansing and a person’s visual impression of shine are related but different endpoints. A Sebumeter reading does not itself measure a product’s visual finish, which can depend on the vehicle and lighting (Draelos, Matsubara & Smiles, 2006).

Use the evidence for what it says: a possible, formula-specific change in measured oil over several weeks (Draelos, Matsubara & Smiles, 2006). Do not turn it into “niacinamide stops oil,” an acne claim or a universal high-percentage recommendation.

What remains uncertain

No robust dose-response trial comparing common niacinamide strengths on visible shine was located. The primary study also had Procter & Gamble research-and-development affiliations, so the commercial relationship belongs in the evidence context (Draelos, Matsubara & Smiles, 2006).

If a formula causes persistent burning, flushing, swelling or a spreading rash, stop and seek clinical advice. This page does not diagnose or treat an oily-skin condition.

Sources

This page summarizes published research. It is not a product review or medical advice.