Squinting

Squinting is the act of partially closing the eyelids. People squint to improve visual clarity, reduce glare, or convey concentration or skepticism. It is a common, usually voluntary behavior, though it can also signal an underlying eye issue when frequent or persistent.

Physiologically, squinting narrows the open area formed by the eyelids, which reduces incoming light and can increase depth of field. The resulting pinhole-like effect minimizes blur from optical imperfections and can temporarily sharpen distant or blurred images, particularly in people with refractive errors.

Common reasons include bright light, eye strain, fatigue, or uncorrected refractive errors such as myopia, hyperopia, or astigmatism. In children, persistent squinting or blinking may indicate vision problems or strabismus and warrants an eye examination.

Beyond vision, squinting can be a facial expression or a habit. It may also accompany conditions such as dry eye or conjunctival irritation, which temporarily worsen comfort and vision.

If squinting is frequent, painful, accompanied by double vision, redness, or headaches, or occurs in a child, a professional eye assessment is advised to check for refractive errors, misalignment, or other eye health issues.