COMPARATIVE ANALYSIS OF THE EFFECTIVENESS OF TOPICAL AND ORAL POLYPHENOLS ON SKIN AGING IN WOMEN: A SYSTEMATIC REVIEW.
Skin Aging, women, antioxidants, phenolic compounds and meta-analysis.
Introduction: Skin aging in women is mainly correlated with exposure to solar radiation with menopausal events, such as hypoestrogenism. In parallel with the increase in life expectancy, both are associated with the induction of oxidative stress, motivating the signs and symptoms of senescence. The development of phytotherapics based on polyphenols can minimize the unwanted effects of skin wear, highlighting flavonoids. Despite its probable beneficial potential, there are limitations in the literature. Objective: To develop a systematic review of clinical trials, addressing the effectiveness of polyphenol compounds in delaying skin aging in women, comparing oral and topical routes. Methodology: A literature search was carried out in the electronic databases MEDLINE (via PubMed), Cochrane, Embase and Web of Science, published between the years 2012 and 2022. Eligible studies were randomized, double-blind, controlled trials, with the exception of one study that did not include a comparator group. Studies were selected that evaluated the effectiveness of an isolated or combined herbal medicine, which reported the following outcomes: elasticity (R2) and roughness or volume of wrinkles (visiometer or Primos). Results: After retrieving the articles, 13 studies were selected, with a total number of participants ranging from 20 to 120 individuals, composed of healthy women aged between 30 and 65 years, with the predominant inclusion criterion being the presence of wrinkles (usually the Wrinkles score ≥ 3) and with intervention protocol applied on the face. Four studies with low risk of bias and high heterogeneity regarding the plants used were identified. Favorable results were shown in elasticity and roughness, being attested after eight weeks of topical administration, and twelve orally. Conclusion: We emphasize that herbal medicines based on polyphenols have a positive impact on skin elasticity and roughness. In addition to the biomolecule, we emphasize the importance of time and route of administration to achieve the expected effect, since the topical route revealed brevity in the response compared to the oral route. Furthermore, we identified in the literature the diversity of tested compounds and methodological weaknesses, making more methodologically consolidated tests necessary.