The Effects of Chewing Gum in Preventing Eyestrain

الملخص EN

Purpose.

To investigate the effects of chewing gum and tablet candy to reduce eyestrain in healthy individuals.

Materials and Methods.

A double-blinded crossover trial was conducted.

Forty-six healthy individuals (23 men, 23 women) between 20 and 59 years old, feeling eyestrain, were enrolled.

Each 10-year age group included 12 individuals except the 30s group, which included 10 individuals.

A visual task was performed on reading material displayed on a computer screen at a fixed distance for 60 min.

Gum or tablet candy of two pieces were chewed for two 15-min periods starting 15 and 45 min after starting to read.

Subjects chewed gum on Day 1 and tablet candy on Day 2, and vice versa.

Primary outcome is as follows: subjective eye fatigue (eye tiredness, eye heaviness, blurred vision, double vision, and eye dryness) using a visual analog scale (VAS).

Secondary outcomes are as follows: subjective accommodation from near and far points of accommodation measured with a D’ACOMO, spherical equivalent refraction, and eye dryness by analyzing ring break-up time (RBUT) measured with the RT-7000 Auto Ref-Topographer.

Results.

The VAS scores of subjective eye fatigue were not significantly changed between chewing gum and tablet candy (P=0.397-P=0.909).

Those scores of eye tiredness and eye heaviness were significantly longer before and after the visual task with tablet candy (P=0.013 and P=0.025, respectively) but not with chewing gum.

The changes of subjective accommodation were significantly lower after the visual task between chewing gum and candy (P=0.043).

There were significant differences among each age group (20 s vs.

30 s, P=0.594; 20 s vs.

40 s, P=0.002; 20 s vs.

50 s, P=0.002).

After reading, the changes of spherical equivalent refraction did not indicate a shift toward myopia (P=0.267).

In the RBUT, there were no significant differences between the samples (P=0.680).

Conclusions.

Chewing gum helps improve the ability of the eye to focus, especially in young adults.