London: Myopia is on the rise. In the UK, the number of children with myopia has doubled in the last 50 years. Globally, it’s projected that by 2050 half of the world’s population will be myopic.
Although myopia – also known as near-sightedness or short-sightedness – can run in families, environmental factors, such as spending too much time indoors have a large influence.
For most people, myopia develops from a mixture of both genetics and environmental factors. But while evidence shows that modern lifestyle factors contribute to myopia, scientists still aren’t entirely sure why.
For instance, research shows that the amount of time a child spends outdoors can play a significant role in their risk of developing myopia.
Not only do most studies show that children who spend more time outdoors are less likely to develop myopia, studies requiring children to spend extra time outdoors during school hours have shown the rate of myopia onset decreased compared with children who didn’t spend additional time outdoors.
But researchers still aren’t quite sure why this is the case. One theory is that the higher levels of light outdoors releases more dopamine into our retinal receptors (the nerves that process light signals in the eye), thus protecting against myopia.