Two superior antioxidants: Ferulic acid and ascorbic acid in reducing signs of photoaging-A split-face comparative study

The assessment of the signs of photoaging in mexametric (melanin and erythema index), corneometric (hydration level), and cutometric (elasticity) examination after the treatment with ascorbic acid and ferulic acid. This study was conducted in a group of 20 women aged 39-61 (mean age 54), with Fitzpatrick skin types II and III. The study included a series of eight treatments performed once a week. Two layers of peeling, based on 14% ferulic acid (left half of the face) and 12% l-ascorbic acid serum (right half of the face) were applied. To determine skin parameters: moisture, elasticity, melanin level, and erythema intensity, the Multi Probe Adapter Systems (Courage + Khazaka electronic GmbH, Koln, Germany) were used. Additionally, before and after the series of treatments, photographs were taken with the standardized photographic system Fotomedicus (Elfo (R)). The results of mexametric measurement for melanin level and erythema intensity were statistically significant (p < 0.0001) for both acids. Slightly greater lightening of the skin was demonstrated for ascorbic acid. The results of corneometric measurement of hydration level for ferulic acid and ascorbic acid were both statistically significant (p < 0.0001). First beneficial changes in improved elasticity could be observed as early as after 8 weeks but the increase in flexibility grew with time (after 12 weeks). These changes affected both acids and all measurement points. The changes in parameters were highly statistically significant (p < 0.0001). Based on the conducted research, it is not possible to state which of the tested acids is more effective in reducing the symptoms of photoaging. Both acids (ascorbic and ferulic), which have a high antioxidant potential, affect the measurable parameters of the skin: pigmentation (melanin index), erythema (erythema index), skin hydration, and elasticity.