Prevention of skin aging processes is one of the main issues in contemporary cosmetology and aesthetic medicine. Protection against the effects of external factors such as UV radiation, air pollution, and free radical scavenging plays an important role. The compounds with proven antioxidative efficacy include ferulic acid. Initially, it was used in cosmetics as a stabilizer of other commonly known antioxidants such as vitamin C and vitamin E. Research shows, though, that this compound is not only used as an additional compound, but also an active ingredient with antioxidative properties, which supports intracellular antioxidant defense systems. Thanks to this, ferulic acid has a protective role for the main skin structures (keratinocytes, fibroblasts, collagen, elastin), which is used in antiaging cosmetic formulations. Due to its ability to inhibit the main enzyme of melanogenesis (tyrosinase), it is also used in anti-blemish cosmetic formulations.
Ferulic acid is used in skin-lightening preparations because it inhibits tyrosinase activity (an enzyme involved in melanogenesis) and inhibits melanocytic proliferation.Staniforth et al.noted that ferulic acid absorbs UV (290–320 nm). In order to increase the lightening effect, ferulic acid can be combined with other compounds that also have a brightening effect, but by other processes such as niacinamide (inhibits the movement of melanosomes from melanocytes to keratinocytes). Saint-Leger et al.reported better effects of ferulic acid after adding to it a keratolytic agent such as lipohydroxycarbones.
Ferulic acid is widely applied in skin care formulations as a delayer of skin photoaging processes and photoprotective agent. Its application as a topical antioxidant has become an important administration route due to maintaining a high local concentration and the low cutaneous metabolism.Moreover, local ferulic acid penetrates deeply into the skin, both acidic and neutral pH, in dissociated and non-dissociated form. Saija et al.studied the penetration of ferulic and caffeic acid soluble in saturated aqueous solutions (pH 3 and pH 7.2) by a human skin cut in the Franz cells. It turned out that these acids, regardless of pH, penetrated the stratum corneum. It was noted that ferulic acid has a slightly better penetration capacity, which was explained by the known higher lipophilicity of this acid. Research on phenolic antioxidants has shown that ferulic acid improves the chemical stability of L-ascorbic acid and α-tocopherol preparations, thereby increasing its photoprotection properties.
Ferulic acid is used in the production of face masks, as well as antioxidant, protective, and moisturizing creams/lotions. The recommended acid concentration in cosmetic products of this type is from 0.5 to 1%. Ferulic acid is also used in medical cosmetology and aesthetics salons. It is most often used at a concentration of 12% and in combination with vitamins C and hyaluronic acid. Ferulic acid is used in the following procedures: microneedling and non-needle mesotherapy, chemical peels, and grooming treatments. Indications for the use of ferulic acid include skin aging and photoaging, hyperpigmentation (melasma), seborrheic skin, and acne.