Randomized, crossover clinical efficacy trial in humans and mice on tear secretion promotion and lacrimal gland protection by molecular hydrogen.

Abstract

Dry eye disease, driven by aging and widespread digital device use, involves tear-film instability and osmotic stress-induced inflammation. This randomized crossover study examined whether a sustained hydrogen-generating supplement could address both pathologies. In 10 human participants, oral supplementation significantly elevated exhaled H2 concentration (p<0.01), improved tear stability (p<0.01), and reduced dry eye symptoms (p<0.05). Parallel mouse experiments demonstrated that H2 administration significantly increased tear secretion in healthy animals (p<0.05) and suppressed tear volume reduction in a murine dry eye model (p=0.007). The findings suggest that molecular hydrogen may simultaneously target tear-film instability and lacrimal gland dysfunction, warranting larger-scale investigation.

Mechanism

Molecular hydrogen is proposed to protect lacrimal gland tissue and stimulate tear secretion, thereby simultaneously addressing tear-film instability and osmotic stress-driven inflammation in the ocular surface.