The effects of oral hyaluronic acid on wrinkles and skin dryness Original paper

Hyaluronic acid (HA) is a viscous substance made in the body. This compound is found abundantly in the skin, eyes, and joints and acts as a lubricant for bodily tissues, but HA production declines with age. Can an HA oral supplement improve the appearance of wrinkles and increase skin moisture content in middle-aged men and women?

This 12-week randomized controlled trial enrolled 40 men and women (average age of 44) and assigned them to take either HA (120 mg/day) or a placebo. At baseline, week 4, week 8, and week 12, the researchers assessed skin structure (wrinkling, skin roughness, and scaling), stratum corneum water content, transepidermal water loss, and skin elasticity (at sites on the face, arm, and waist).

Compared to baseline, supplemental HA increased stratum corneum water content and decreased transepidermal water loss (in facial skin only). HA also resulted in increased skin elasticity in facial and arm skin and improved skin structure, specifically in terms of smoothness, scaliness, and wrinkling.

The researchers hypothesized that the effects of HA supplementation would have been apparent by week 4 because skin cells turn over over every 28 days, but most of the skin changes measured were not apparent until week 8.

Three of the study's seven authors declared conflicts of interest.