Hydrogen-producing milk to prevent reduction in tear stability in persons using visual display terminals.

PURPOSE

To examine the effect of hydrogen (H)-producing milk, which induces H production by intestinal microbiota, on the prevention of dry eye disease.

METHODS

A randomized, double-blind, placebo-controlled, parallel-group comparative study was conducted in humans. Of 118 candidates aged 20-60 years who were using visual display terminals daily, 54 subjects (mean age, 42.4 years) with mild-to-moderate dry eye symptoms, who were not dry eye patients based on the 2006 Japanese Diagnostic Criteria for Dry Eye, were included in the study. Subjects were assigned to the H-producing milk group or the placebo group. They were instructed to ingest the assigned test beverage once per day for three consecutive weeks. Breath H concentration, fluorescein tear film breakup time (fTBUT), Schirmer's test, 8-OHdG concentration in tears, reported ocular symptoms using the dry eye-related QOL score questionnaire, and the visual analogue scale were assessed at weeks 0 and 3.

RESULTS

Change in fTBUT in the H-producing milk group was significantly greater than that in the placebo group. A significant decline in fTBUT was observed in the placebo group (p = 0.04), but not the H-producing group (p = 0.26). This phenomenon was strongly observed in females. We found a positive correlation between the change in fTBUT and net H production, and a negative correlation between the change in 8-OHdG concentration and net H production in young females.

CONCLUSIONS

H-producing milk appeared to retard the decline in tear stability and may prevent short fTBUT-type dry eye by decreasing oxidative stress in the lacrimal functional unit.