Doctors and nurses are handing out pills to diabetics rather than recommending they lose weight and take more exercise, research suggested.
A study found 36% of people newly-diagnosed with Type 2 diabetes were popping pills within the first month of knowing they had the condition.
International and UK guidelines say people with Type 2 should be given advice on managing their weight and taking up exercise before medication is prescribed.
A total of 2.25 million people in the UK are diagnosed with Type 2 and another 500,000 are thought to be undiagnosed.
Dr Rob Andrews, a researcher on the study, which is being presented at Diabetes UK's Annual Professional Conference in Glasgow, said he believed a lack of staff training, too few dieticians and government targets on managing diabetes were to blame.
One part of the problem was the Quality and Outcomes Framework (QOF) which rewards GP practices for managing diabetes well, he said.
He added: "If you don't give patients the chance to understand their disease and don't let them try and control it with diet and exercise, evidence shows that for all the time they have diabetes, they don't focus on diet and exercise. We know that during diagnosis is the time when people may actually take action on those things."
Dr Andrews, from Bristol University, said one UK-based study had shown that 25% of people diagnosed with Type 2 managed to control their diabetes in the first year without the need for medication. "This was in the 1980s when they were given simple advice on diet and exercise, it wasn't even intensive," he said.
A spokeswoman for the Department of Health said: "Prescribed medication is vital to enable many people with diabetes to manage their condition on a day-to-day basis and to reduce their risk of developing complications such as heart attack and stroke.
"However, good diabetes care is not just about medication. As the Nice guidelines recommend, people with Type 2 diabetes should be encouraged to make lifestyle changes, such as healthy eating and increased physical activity, before starting medication."
