A Randomized, Double-Blind, Placebo-Controlled Trial Assessing the Effects of Oral Centella asiatica Extract on Skin...

Centella asiatica has been widely recognized for its dermatological benefits; however, clinical evidence supporting the efficacy of oral supplementation for improving skin aging parameters remains limited. This randomized, double-blind, placebo-controlled study evaluated the effects of oral Centella asiatica extract on skin wrinkles and related skin parameters in middle-aged women.

A total of 112 participants were randomized to receive either Centella asiatica extract (200 mg/day) or placebo for 12 weeks. Skin wrinkle parameters were quantitatively assessed using a three-dimensional skin imaging system (PRIMOS^®). Skin hydration, transepidermal water loss (TEWL), elasticity, and skin color (brightness and redness) were additionally measured using validated non-invasive instruments. Efficacy analyses were performed in the per-protocol population.

After 12 weeks of supplementation, the Centella asiatica extract group demonstrated significant improvements in multiple wrinkle parameters compared with the baseline. Average wrinkle depth decreased by 11.1%, and the mean depth of the largest wrinkle decreased by 14.4%. Maximum wrinkle depth and total wrinkle volume were reduced by 13.3% and 13.7%, respectively, while surface roughness (Ra) decreased by 10.4%. In contrast, the placebo group showed minimal or inconsistent changes. Epidermal hydration at the cheek site significantly increased, while transepidermal water loss decreased, indicating improved skin barrier function. However, the magnitude of changes in epidermal hydration (2.7%), skin elasticity (R2; 0.7%), and skin brightness (L*; 0.7%) were relatively small. Skin elasticity and skin brightness showed statistically significant differences compared with the placebo group (p < 0.05), but these changes should be interpreted as modest improvements. No serious adverse events were reported, and all hematological and biochemical safety markers remained within normal reference ranges during the 12-week intervention period.

Oral supplementation with Centella asiatica extract for 12 weeks was associated with improvements in wrinkle-related parameters and TEWL, while changes in skin hydration, elasticity, and brightness were modest and of limited magnitude. These findings suggest a potential role for short-term supplementation; however, further studies are required to confirm long-term efficacy and broader applicability.