The Serum That Works Where Others Stop - Meet 5-ALA

Most serums work on the surface. The Kiyomi Skin Niacinamide Serum works deeper. 5-ALA — the cellular energy ingredient studied in Japanese dermatology for over two decades — activates your skin's natural renewal process. Paired with 5% Niacinamide and Hydrolyzed Hyaluronic Acid, the result is visibly refined pores, a more even complexion, and hydration that actually holds.

Why Niacinamide Works — And Why 5% Is The Right Dose

Niacinamide, also known as Vitamin B3, is one of the most research-backed active ingredients in modern skincare. It works on multiple levels simultaneously: it visibly refines pore appearance, evens skin tone, reduces redness, regulates sebum production, and strengthens the skin's moisture barrier — all without irritating even sensitive skin.

The question most often asked: why 5%, when other brands use 10%?

The answer is in the science. In a landmark double-blind, placebo-controlled split-face clinical study published in Dermatologic Surgery (Bissett et al., 2005), 50 subjects applied 5% niacinamide twice daily for 12 weeks. The results showed significant, measurable improvements across fine lines, skin texture, hyperpigmented spots, red blotchiness, and skin elasticity - all at the 5% concentration. A second peer-reviewed study by the same research group (International Journal of Cosmetic Science, 2004) confirmed the findings across a broader range of skin aging markers.

Higher concentrations do not equal stronger results. Formulations above 5–7% have been associated with increased rates of flushing and irritation in daily use — particularly in combination serums — without delivering measurably superior outcomes for pore refinement or skin tone. 5% niacinamide is the clinically validated sweet spot: effective enough to produce visible change, gentle enough for twice-daily use on all skin types.

In the Kiyomi Skin Niacinamide Serum, 5% niacinamide works in synergy with 5-ALA to amplify these results: where niacinamide refines and evens at the surface level, 5-ALA supports the cellular renewal process underneath — so the two ingredients compound each other's effect over time.

5-ALA: The Ingredient That Changes How Your Skin Behaves

Most skincare works from the outside in. 5-ALA works differently. As a precursor to cellular energy production, it supports your cell's mitochondrial activity, boosting natural cell renewal, collagen synthesis, and moisture retention. The result isn't just surface hydration. It's skin that progressively performs better. 

Daily Use, Compounding Results

Unlike one-dimensional serums, the Niacinamide Serum is designed to deliver cumulative benefits:

Day 1:

lighter, more hydrated skin.

Week 2–3:

visibly reduced pore size and more even tone.

Week 4+:

clinical studies on 5-ALA show measurable improvement in skin moisture and a reduction in fine lines. The longer you use it, the more your skin responds.

Join thousands of customers who've made this their daily essential.

Dermatologically tested. Cruelty-free. 

Sources: Bissett DL et al., "Niacinamide: A B Vitamin that Improves Aging Facial Skin Appearance," Dermatologic Surgery, 2005; Bissett DL et al., "Topical niacinamide reduces yellowing, wrinkling, red blotchiness, and hyperpigmented spots in aging facial skin," International Journal of Cosmetic Science, 2004.

For a plant-derived retinol alternative, explore our Bakuchiol Serum.