A study has called into question the use of diabetes treatments in the early stages of the disease.
The report, published in the New England Journal of Medicine, revealed that people suffering from type two diabetes may not benefit from the two most common drug treatments.
Instead, the study advises that patients should be encouraged to improve their diets and take more exercise.
Dr Victoria King, research manager at Diabetes UK, commented: "The front-line of defence for someone at risk of type two diabetes would be diet and exercise treatment. This should be considered first and has shown to be most effective in delaying or preventing the progression to type two diabetes.
"The drug treatments tested in this study are proven to be effective once someone has type two diabetes but as the results of this study show, not as effective in people at risk of the condition."
The large-scale study looked at around 9,000 people, among whom exercise and diet proved to be the most effective methods of preventing the development of the disease.