Are you getting enough violet light?

This weekend is not only your last chance to polish off your bear-hunting on The Big Sleuth public art trail across Birmingham and surrounding areas but a bear-illiant way of getting all-important violet light. Read our expert Dr Nicola Logan’s view on why getting outdoors for 90 minutes a day may reduce children’s risk of developing short-sightedness. 

Most people think of myopia – the medical term for short-sightedness – as an inconvenience because the blurred vision it causes is easily corrected with glasses or contact lenses.

Yet, short-sightedness is a global public health problem, according to Aston University’s Dr Nicola Logan, a senior lecturer in the School of Life and Health Sciences optometry department.

This is because a myopic eye is a longer eye and so the light sensitive part at the back of the eye is stretched, which can lead to a number of eye diseases in later life, such as glaucoma, maculopathy and retinal detachment.

Dr Nicola Logan

Experts are also concerned because the number of people with myopia is increasing. Research suggests that by 2050 it will affect half the world’s population.

Myopia normally develops in children and increases in prevalence and amount during the teenage years. About 30 per cent of teenagers in the UK have myopia, and in some East Asian countries around 80 per cent of teenagers have myopia. 

Our visual environment plays a role in myopia development. Lifestyles have changed significantly over the last 50 years, with greater time being spent indoors on computers, tablets and smartphones.

“The LEDs and fluorescent lights often used in our homes and schools contain little violet light, and violet light does not pass through materials such as the UV-protected spectacles and the glass in windows,” explains Dr Logan. “Research suggests that it is lack of time that children spend outdoors that seems to trigger myopia development.

“The impact of these levels of myopia on all areas of society is enormous due to the cost of eye examinations, glasses and treatment of eye disease. The reasons why myopia develops are not fully understood; the prevalence has increased too quickly to be explained solely by genetics.

 “At Aston University, we are looking for ways to prevent myopia, or, if it has started, at ways to slow its progression.

“Spending greater time outdoors – 90 minutes a day – seems to reduce the risk of developing myopia. Why this works is not clear. The most recent research suggests that it may be the lack of visible violet light indoors that causes the problem and if we spend time outdoors in daylight we are exposed to ample violet light.”

“If myopia has already developed, then we can slow progression by about 50 per cent by using different designs of contact lenses or a low dose of atropine eye drops. Spending more time outdoors may also help slow down progression of myopia in children.

“We do not have all the answers to why and how myopia develops, but we do have ways we can slow down myopic progression. It is time that we stop just correcting the blurred vision in myopia and start actively managing and controlling it.” 

*A version of this article first appeared in The Conversation in 2017

Paws for thought

  • The Big Sleuth public art trail launched on Monday 10 July 2017 and runs for 10 weeks, culminating on Sunday 17 September. It follows the phenomenal success of The Big Hoot in 2015, which raised over £500,000 for the Birmingham Children’s Hospital Charity.  The campaign focuses on tracking down 237 individually-designed sun bear and bear cub sculptures across Birmingham and surrounding areas including Sutton Coldfield, Solihull, Sandwell and Resorts World. The campaign trail is designed to promote getting outdoors and exercising as a family, whilst also enjoying tracking down the bears and fundraising.  
  • Aston Medical School has its own bear on the trail – Ed The X-ray Bear – located on the Aston University campus. X-ray Ed, was designed by Birmingham artist and former radiographer Anne Guest who chose her X-ray theme to highlight the work of Dr John Hall-Edwards who pioneered the use of X-ray in surgery at Birmingham General Hospital over 120 years ago. The hospital building is now the home of Birmingham Children’s Hospital.