More than one in 20 people who completed a questionnaire on type 2 diabetes risk already had the condition, it has emerged.
A survey of 1,000 people who filled in a Diabetes UK assessment found 6% said they went on to be diagnosed by a GP after being identified as at high risk of the condition.
“Half of people with type 2 already having signs of complications by the time they are diagnosed”
The charity said the findings showed the potentially “life-changing” positive impact of undergoing a risk assessment, either through its online questionnaire or in pharmacy or GP surgery.
Risk factors include being over 40 or over 25 if from a South Asian, African Caribbean, or Chinese background, having a close relative with diabetes, being overweight or having a large waist.
In the UK there are 3.2 million people living with type 1 and type 2 diabetes, a condition where there is too much glucose in the blood because the body cannot use it properly. A further 630,000 are estimated to have type 2 diabetes but are undiagnosed.
It is thought that up to seven million people are at high risk of developing type 2 diabetes – and if current trends continue, an estimate five million peple will have the condition by 2025.
Barbara Young, chief executive of Diabetes UK, said: “If left unchecked, type 2 diabetes can lead to devastating health complications such as amputation, blindness and stroke.
“This is why it is so important that people with type 2 are diagnosed as quickly as possible so that they can start getting the education and healthcare they need to manage it.
“At the moment, too many people with the condition are not being identified quickly enough and this is why half of people with type 2 already having signs of complications by the time they are diagnosed,” she said.
“This is why we need to do more to reach the estimated 630,000 people who have it but do not know it,” she added.