It is strongly linked to obesity and lack of exercise and it can lead to heart disease and strokes.

But now about 1,400 people across Norwich parts of Norfolk have taken part in an NHS Diabetes Prevention Programme designed to help them prevent the onset of the disease through healthier living.

Among them is Glenys Gray, 77, who attended one of the courses' sessions at North Walsham Community Centre.

The Sheringham resident said the programme had taught her much about healthy eating that was not widely understood when she was younger.

Mrs Gray said: 'Things are so different now to what we were told years ago. For example we used to be told that butter was bad for you and you should eat margarine, but now a bit of butter is considered healthier.'

Another participant, David Willer, of North Walsham, said he joined the course after his GP found his blood sugar level to be too high.

Mr Willer, 66, said he had also enjoyed finding out about how he could live more healthily.

He said: 'It makes you more aware of what you are putting in your mouth and makes you think twice about doing some things. Now when I go out and buy a portion of fish and chips, I'll think again about the chips.'

The course lasts six months - including weekly sessions for the first seven weeks followed by monthly meetings.

The programme focuses on Type 2 diabetes, which covers roughly 90pc of all people with diabetes. Each year, the disease costs the NHS £8.8 billion - almost 9pc of its budget - and annually causes 22,000 early deaths.

Suzanne Wilkin, a health and wellbeing coach who runs the courses, said: 'People have been making a huge amount of changes in so many different areas. They love the groups because they're so supportive and people share their experiences.'

People at risk of diabetes can be referred onto the programme though their GP surgery.

Participants are given a plan designed to cut the risk of developing Type 2 diabetes through education, weight loss, improved diet and increased levels of exercise.

There are currently five million people in England at high risk of developing Type 2 diabetes. If these trends persist, one in three people will be obese by 2034 and one in 10 will develop Type 2 diabetes.

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