People who swallow hyaluronic acid supplements—whether they’re big or small molecules—tend to have moister skin, which suggests the size of the molecule doesn’t matter for this effect.

Taking hyaluronan pills every day for about a month or two may help make dry skin on your face and arms more moisturized, according to studies done on Japanese adults.

Taking hyaluronic acid by mouth might help keep your skin more hydrated, especially if you're Chinese or have mixed heritage, but the studies so far aren't very reliable.

Taking a daily supplement of hyaluronan for 12 weeks can make your face more hydrated, with a noticeable 10.9% boost in skin moisture compared to not taking it—this also helps your skin stay protected and lose less water.

Taking a daily supplement of hyaluronan for 3 months may make your skin look shinier and feel softer, at least according to how people felt about it — but it didn’t work any better than a fake pill.

Taking a daily supplement of hyaluronan for 12 weeks can make your skin feel tighter and more bouncy on your forehead, arms, and waist—especially at your waist, where it improved by 38% compared to people who didn’t take it.