Mechanistic Insights into the Multiple Functions of Niacinamide: Therapeutic Implications and Cosmeceutical Applications in Functional Skincare Products

Abstract

Niacinamide (or nicotinamide) is a small-molecule hydrosoluble vitamin with essential metabolic functions in mammalian cells. Niacinamide has become a key functional ingredient in diverse skincare products and cosmetics. This vitamin plays a pivotal role in NAD⁺ synthesis, notably contributing to redox reactions and energy production in cutaneous cells. Via diversified biochemical mechanisms, niacinamide is also known to influence human DNA repair and cellular stress responses. Based on decades of safe use in cosmetics, niacinamide recently gained widespread popularity as an active ingredient which aligns with the "Kligman standards" in skincare. From a therapeutic standpoint, the intrinsic properties of niacinamide may be applied to managing acne vulgaris, melasma, and psoriasis. From a cosmeceutical standpoint, niacinamide has been widely leveraged as a multipurpose antiaging ingredient. Therein, it was shown to significantly reduce cutaneous oxidative stress, inflammation, and pigmentation. Overall, through multimodal mechanisms, niacinamide may be considered to partially prevent and/or reverse several biophysical changes associated with skin aging. The present narrative review provides multifactorial insights into the mechanisms of niacinamide's therapeutic and cosmeceutical functions. The ingredient's evolving role in skincare was critically appraised, with a strong focus on the biochemical mechanisms at play. Finally, novel indications and potential applications of niacinamide in dermal fillers and alternative injectable formulations were prospectively explored.

Keywords: antioxidants; cellular respiration; cosmeceuticals; dermal fillers; formulation; functional ingredients; hyaluronic acid; niacinamide; skincare; viscoelastics.

Figure 1

Molecular structures of niacin and niacinamide in the vitamin B3 complex and their molecular constitutive role in NAD⁺ synthesis. NAD⁺, nicotinamide adenine dinucleotide.

Figure 2

Mechanistic overview of the intracellular antioxidant mechanisms of niacinamide within the ROS cascade. The key enzymes involved in the cascade are depicted in grey boxes. The inhibitory effect of niacinamide on these enzymes is illustrated in red. Conversely, the stimulatory effect of niacinamide is represented by green arrows.

Figure 3

Overview of key cutaneous processes influenced by niacinamide and the resulting biological functions. The diagram provides a concise overview of niacinamide’s multifaceted impact on skin health and its role in mitigating the observable aging process.

Figure 4

Niacinamide formulation variants and their permeation/administration into the skin. The aqueous formulation (A) is highly limited as regards penetration in the stratum corneum. However, an oil-in-water formulation (B) is characterized by enhanced niacinamide permeation into the epidermis. For a more direct impact on the dermis, aqueous solution (C) and hydrogel (D) intradermal injections could offer increased niacinamide bioavailability and effectiveness.