Yes, sweat can damage your eyes. Sweat contains salt, which can irritate the eyes, and it is slightly acidic, compared to the eye's fluid. Additionally, sweat contains oils and hormones that can irritate the cornea and surrounding eye tissue, causing redness and inflammation. Sweat can also carry bacteria, hair, and cosmetic products that are never supposed to get in your eyes, risking potential infections. If sweat gets into your eyes, it can cause eye irritation, burning, blurring vision, or stinging, and in rare cases, it can even lead to eye infections or allergies. To prevent sweat from getting into your eyes during workouts, it is a good idea to wear a sweatband to stop the fluid from getting into the eyes, and to wear a ventilated baseball cap with a liner, and apply a thin line of clear lip balm or petroleum jelly above your eyebrows.