Almost one in 70 people are living with undiagnosed diabetes and are running the risk of \"devastating\" complications, the UK\'s leading diabetes charity said, Monday. There are an estimated 850,000 cases of undiagnosed Type-2 diabetes in Britain, meaning about one in 74 people has it but does not know, according to Diabetes UK. That equates to at least one passenger on a full double-decker bus or about 1,000 people in a full Wembley Stadium having undiagnosed diabetes, it said. Sufferers are missing vital health checks and those who leave the condition untreated run a greater risk of complications such as amputation, blindness, kidney failure, and stroke. Risk factors for Type-2 diabetes include being overweight, having a large waist, and being physically inactive. Older people and people from a black or South Asian background are also at higher risk, as are people with a family history of the condition. To mark the start of Diabetes Week, the charity and healthcare specialists Bupa was today attempting to break the world record for the number of waists measured in eight hours. The record attempt was launching a series of roadshows around the country where teams will refer people who are at high risk to their GP. This will mean that people who have the condition can be diagnosed and those who do not have it but are at high risk can be given the advice and support to help prevent it. Diabetes is a condition in which the amount of glucose in the blood is too high because the body cannot use it properly. Type-2 diabetes develops when the body can produce some insulin, which breaks down glucose, but not enough, or when the insulin that is produced does not work properly. Summing up the aim of this initiative, Health Minister Simon Burns said, \"We are working with the health authorities to improve diagnosis rates for diabetes.\"