A Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Effects of a Polyphenol-Rich Fruit Extract Combined with Biotin on Wrinkle Morphology, Skin Surface Roughness, and Hair Shedding

Polyphenol-rich botanical extracts have emerged as promising nutricosmetic interventions against signs of skin aging. Fruit polyphenols improve skin appearance, while biotin plays a recognized role in keratin synthesis and hair follicle metabolism, yet their combined effects have not been evaluated. This study assessed the effects of a red- and blackcurrant polyphenol with biotin supplement (RiboBeauty®) in a randomized, double-blind, placebo-controlled trial. Fifty-four women were randomized, and fifty-two were eligible for the efficacy analyses (Placebo, n = 27; Supplement, n = 25). Over 12 weeks, wrinkle morphology and skin roughness were quantified by 3D imaging and hair shedding by a combing test. For skin roughness, mean local peak-to-peak amplitude (Stm) showed significant within-group reductions in the supplement group at D56 (−4.897%; p = 0.0489) and D84 (−6.558%; p = 0.0491), without significant between-group differences. Hair shedding was significantly lower in the Supplement group versus Placebo at D28 (−30.90%; p = 0.0203) and D56 (−41.58%; p = 0.0158), although the treatment × time interaction was not significant. The crow’s feet wrinkle area showed numerically (but non-statistically significant) lower values in the supplement group than in the placebo group at all post-baseline visits. Overall, these findings indicate a favorable efficacy signal, while the limited demonstration of statistically significant placebo superiority across the main skin outcomes warrants cautious interpretation.