A study by Kawada et al. (2014) investigated the effect of hyaluronic acid on dry skin. This was a randomized, double-blind and placebo-controlled study with 64 participants. One group received 120 mg of hyaluronic acid daily for 12 weeks, the other group a placebo.
The study showed that when taken orally through dietary supplements, both small and large hyaluronic acid molecules are bioavailable and absorbed into the tissue. The study participants who took hyaluronic acid had a significant improvement in their skin. The skin had more moisture and elasticity compared to the placebo group.
The research team concluded that hyaluronic acid can help with dry skin because it increases moisture and improves the skin.
Source: Kawada, C. et al. 2014. Ingested hyaluronic acid moisturizes dry skin. Nutrition Journal, 13:70.