Olympic hero Sir Steve Redgrave is backing a new campaign to raise awareness of the risk among diabetics of going blind.

The sportsman, who won five gold medals for rowing, was diagnosed with type 1 diabetes in 1997.

He backed a new campaign to raise awareness of retinopathy, which is a leading cause of blindness in the UK.

Retinopathy is a complication of diabetes (type 1 or 2), where blood vessels in the retina become blocked or leaky, or grow in an abnormal way.

If left undetected or untreated, the condition leads to impaired vision and can ultimately lead to blindness.

The campaign, from Specsavers opticians and the charity Diabetes UK, comes as a survey of almost 2,000 diabetic children showed a quarter had not been screened for retinopathy in the last year.

Sir Steve said: "This statistic is particularly worrying as the worst possible outcome of diabetic retinopathy - blindness - can be avoided through digital screening and early detection.

"Young people with diabetes have their whole lives ahead of them and should take all the measures they can to minimise the impact of the condition.

"I know only too well the shock of being diagnosed diabetic and the potential consequences it can have on your daily life. However, I have learned that the condition is manageable and the extreme consequences, such as blindness, can be preventable. I would urge every diabetic, young and old, to have their eyes screened every year to minimise their risk of visual impairment."

Diabetics are 20 times more likely to go blind than those without the condition and up to 40% of the 2.2 million diabetics in the UK have varying degrees of retinopathy.

Good treatment can prevent blindness in 90% of those cases as long as the condition is detected early enough. Douglas Smallwood, chief executive of Diabetes UK, said: "Research around retinal screening is essential to stop people's lives being devastated by retinopathy."