Redness: Why use Niacinamide?

To alleviate mild discomfort and reduce redness, niacinamide is often recommended. Indeed, several published reports have shown that niacinamide can mitigate the persistent inflammatory state of the skin, making it a promising active ingredient for skin conditions with an inflammatory component such as eczema, rosacea, acne, and so on.

Niacinamide can be beneficial for mild to moderate stages. However, severe cases require other treatments. In all instances, seek advice from a healthcare professional.

• A prospective, multicenter, open-label (without a control group) cohort study evaluated the efficacy of a pharmaceutical tablet marketed under the name Nicomide (750 mg of nicotinamide, 25 mg of zinc, 500 μg of folic acid, and 1.5 mg of copper) administered orally to 198 patients suffering from common acne or rosacea. After a treatment period of four to eight weeks, the majority of subjects reported a significant reduction in their inflammatory lesions according to self-assessment.

• An in vitro trial has shown that niacinamide significantly reduced the secretion of IL-8 in a dose-dependent manner through the NF-kB and MAP kinase pathways by interacting with the TLR-2 receptor on the surface of epidermal cells in a model of human keratinocytes stimulated by Propionibacterium acnes.

• A double-blind, placebo-controlled clinical trial conducted on 44 female panelists with phototypes II and III demonstrated that the daily topical application of a 5% niacinamide oil-in-water emulsion system for two weeks significantly reduced the intensity of erythema and the level of inflammation caused by acute exposure to UV rays, compared to untreated exposed sites.

• A pilot study involving 16 patients with light phototypes suffering from active inflammatory acne on their backs demonstrated that the topical application of a product containing 4% niacinamide, 1% retinol, and 0.5% 7-dehydrocholesterol in a moisturizing base led to a significant downregulation of the expression of three inflammatory genes (IL-6, MCP-1, and MIF) in acne-affected areas after 45 days.

• An observational study revealed that the twice-daily application of a gel containing 0.25% of N-methyl-nicotinamide, a metabolite of nicotinamide, led to an improvement in the signs of rosacea (burning, tingling, number of papules and pustules, and the intensity of erythema) in 76% of cases (n = 34) over the four-week study period compared to the absence of treatment as a control.

Contact a healthcare professional if "home remedies" do not improve the issue or if you present other symptoms, such as a fever.

What are the molecular mechanisms that underlie its anti-inflammatory action?

The niacinamide exerts anti-inflammatory properties through the control of the transcription of signaling molecules mediated by NF-kB by inhibiting the activity of PARP-1 in a dose-dependent manner, an enzyme playing a significant role in the repair of nuclear DNA and the expression of inflammatory factors. This results in a decrease in the genetic expression of certain chemokines and cytokines, chemical messengers that trigger inflammation, including IL-6, IL-8, MCP-1, and TNF-α, induced by stress factors (sun exposure, cigarette smoke, air pollution, etc.).

An anti-inflammatory action affecting the chemotaxis of neutrophils has also been reported for niacinamide by reducing the production of IL-8 in keratinocytes through the inhibition of MAPK and NF-kB signaling pathways, which reduces inflammation and improves, among other things, redness. It also stimulates the expression levels of anti-inflammatory mediators (IL-10 and MRC-1).

Topical niacinamide also improves the structure of the epidermis. Indeed, it can notably increase the production of ceramides, lipids that help maintain the skin's protective barrier, as well as other lipids contained in the intercellular spaces of the stratum corneum in order to restore the barrier function of the epidermis, resulting in a decrease in irritations when the skin is exposed to environmental stress factors and therefore less redness, which adds to its anti-inflammatory effects.

Thanks to its high safety profile and its numerous modes of action to improve the skin's condition, niacinamide is widely used topically as an anti-inflammatory agent, and has been for several decades. Indeed, many cosmetic products have begun to incorporate this water-soluble derivative of vitamin B3 into their formulas. Present in serums, creams, cleansers, and many other forms, niacinamide can be used with other active skin ingredients to enhance their effects.

If it is used for its soothing properties to help reduce redness caused by certain conditions, special attention must be paid to its concentration. Various studies focusing on the effect of nicotinamide on skin conditions marked by inflammation, such as acne or rosacea, use products containing doses of 4 to 5% niacinamide and for a duration of four to eight weeks.