Nicotinamide can inhibit melanin body from melanocyte to keratinocytes transshipment, but will not reduce the activity of tyrosinase or cell proliferation, thus affecting the skin pigmentation, and nicotinamide can interfere with the keratinocytes and melanocyte signals between channels, it can also reduce the melanin has generated, reduce melanin to the transfer of surface cells.
When nicotinamide is used as a whitening ingredient, it has a certain effect on reducing melasma and pigmentation caused by ultraviolet rays when used at a concentration of 2% ~ 5%. It is said that nicotinamide and N-acetyl glucosamine combined use, whitening effect is better, also some people think that nicotinamide has an anti-glycation effect, can fade the yellow skin after glycation protein, help to improve the yellow dark complexion.
The use of 5% nicotinamide can reduce aging problems such as wrinkles, erythema, yellowing, and discoloration on the facial skin, which may be related to the ability of nicotinamide to stimulate collagen production.
Topical nicotinamide can increase the levels of free fatty acids and ceramides in the skin, stimulate dermal microcirculation, prevent skin moisture loss, promote protein synthesis, increase the intracellular NADPH level, and accelerate the differentiation of keratin cells. In addition, nicotinamide can relieve skin irritation due to surfactants or solvents.
The ability of nicotinamide to improve skin barrier function means that nicotinamide has the moisturizing ability, and topical 2% nicotinamide is better at moisturizing than vaseline.
2% topical nicotinamide can reduce the production of fatty acids and triglycerides in sebum, and play a role in controlling oil secretion. The decrease in oil production also makes skin pores look less large.