When the eyes are working hard for a very long period of time, the strain can cause a number of problems including sore eyeballs, headache, backache, drooping eyelids and blurred vision. Because eyes don’t blink often enough when focusing on a single object, students may also experience uncomfortable dryness in the eyes and prolonged eye strain can make it worse.
 
Short-sightedness or myopia means that a person can easily see things that are close up, but objects at a distance such as the number on a bus or the menu board in a restaurant look blurry. Wearing glasses or contact lenses solves the problem. This is much more likely in children and young adults, whose eyes are still developing, than in older adults. Since their eyes are still growing and the tissues are more pliable, they are more susceptible to long-term change. And the changes could be permanent.

Sometimes children complain of dizziness, headache etc because they need time to take oxygen and blood supplements. So, the reading time must be limited.

Strengthening these muscles with a series of eye exercises will go a long way in preventing eye strain.

The best way to prevent eye strain is to take breaks and do a small exercise of shifting the focus: shift your focus from near to far, then shift it from up close to at least 20 feet away.

Students should not study continuously for long hours. If they relax, close their eyes for some time, breathe properly, blink regularly, and do not diffuse the attention, or stare or squint, they can read as long as they want to with ease.

Sanjay Dhawan is additional director and head, department of ophthalmology, Fortis Healthcare