Effect of 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one-containing lactic acid bacterial beverages on skin moisture: a randomized, double-blind, placebo-controlled, parallel study.

Although we previously reported that 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one has antioxidant properties, its effect on the skin remains unclear. This study aimed to investigate the effects of beverages containing 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one on skin moisture. This study enrolled 220 healthy Japanese participants with dry skin who were randomly assigned to the test or placebo group (n = 110 each). Each group received either a beverage containing 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one or a placebo for 12 weeks. The primary outcome was stratum corneum water content. Secondary outcomes were transdermal water loss, number of blemishes and wrinkles, and blood antioxidant markers such as biological antioxidant potential and diacron-reactive oxygen metabolites. Visual analog scale was used to assess skin improvement. Stratum corneum water content and visual analog scale scores differed significantly between the test and placebo groups. Water content significantly increased in the test group compared to the placebo group at 4 and 8 weeks. Subjective skin symptoms significantly improved with the test beverage intake compared with the placebo. No other significant or adverse effects were observed. In conclusion, the of 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one-containing beverage for 12 consecutive weeks significantly increases stratum corneum water content. The study findings could aid in the development of safe functional foods enriched with this compound.