"Sweat contains salt, which can irritate the eyes. Plus, it's slightly acidic compared with the eye's fluid," Brown explains.
Fortunately, there's no evidence that salt from sweat can harm your eyes, says Stephanie Marioneaux, M.D., a spokeswoman for the American Academy of Ophthalmology. If perspiration is interfering with your workout, wear a sweat band or a moisture-wicking hat or visor to trap forehead moisture before it has a chance to creep down into your eyes. Keep artificial tears on hand to use if you do get an errant drop. (Some good news: sweat spreads happiness! No, really.)
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