Spectacles that are marketed to filter out blue light probably make no difference to eye strain caused by computer use or to sleep quality, according to researchers, including one of Indian-origin. Blue-light filtering lenses, also known as blue-light blocking spectacles, have been increasingly prescribed or recommended, often by optometrists, since the early 2000s.

Researchers from the UK and Australia reviewed data from 17 randomised controlled trials from six different countries and found no evidence that blue-light filtering lenses protect against damage to the retina, the light-sensitive tissue at the back of the eye. "The amount of blue light our eyes receive from artificial sources, such as computer screens, is about a thousandth of what we get from natural daylight. It`s also worth bearing in mind that blue-light filtering lenses typically filter out about 10-25 per cent of blue light, depending on the specific product," Dr Sumeer Singh, a postdoctoral research fellow at the University of Melbourne,