Almost 18,000 people in Norfolk are at risk of losing their sight due to diabetes, research claims.

Olympic rower Sir Steve Redgrave has joined forces with Specsavers and the Royal National Institute of Blind People (RNIB) to warn of the risks of blindness linked to the condition.

Sophie Castell, from the RNIB, said: 'Sadly, all too often, people with diabetes can lose their sight due to complications. Yet with early detection through regular eye tests and specialist diabetic eye screening followed by timely treatment, sight loss due to diabetic retinopathy can be prevented.'

The campaign follows Mr Redgrave admitting that losing his sight is one of his biggest worries, as his diabetes means he is up to 20 times more likely to lose his sight than those without the condition.

Research supported by RNIB reveals that London, Manchester and Liverpool are among the UK cities at greatest risk of blindness due to diabetic retinopathy.