Most school pass-outs in Asian cities are myopic

The researchers' team led by Professor Ian Morgan of Australian National University found an "extraordinary rise" in myopia cases among students, being caused as a result of them working hard in school and missing out on outdoor light.

"They've gone from something like 20 per cent myopia in the population to well over 80 per cent, heading for 90 per cent in young adults, and as they get adult it will just spread through the population. It certainly poses a major health problem," Morgan told BBC news.

The scientists further added that one in five of these students could experience severe visual impairment and even blindness.

Morgan has argued that many children in South East Asia spend long hours indoors studying at school and doing their homework. According to him, two to three hours of daylight exposure is much needed for healthy eyes.

"As a result of massive educational pressures and the construction of a child's day, the amount of time they spend outside in bright light is minimised," he said.

Morgan also cited cultural factors playing their part.

"Across many parts of South East Asia, children often have a lunchtime nap. They are missing out on prime light to prevent myopia," he said.

One is myopic if your vision is blurred beyond 2m (6.6ft), eye-experts said. It is often caused by an elongation of the eyeball that happens when people are young.

Compared to Asian cities, the average level of myopia in UK was found to be between 20 per cent and 30 per cent.