People who squint a lot probably need glasses. This is often a sign of nearsightedness. Nearsighted people who don’t have glasses will squint to sharpen their focus when looking at something far away. Though it may solve the problem temporarily, it can also cause eyestrain and headaches — ant it is not particularly attractive.
Some adolescents tend to squint when they’re growing up. By the time they are 20 or 21, many of them will realize that their nearsightedness is a problem that needs attention.
In some cases. the nearsightedness will have improved by then; in others, it may have gotten progressively worse. For most people, however, the degree of nearsightedness will have reached a plateau by the time they’ve fully grown. The problem may be in one eye or both. Only an eye examination can determine that. Corrective lenses can be prescribed so that squinters no longer have to strain their eyes to see clearly.