The University of Leicester team included GP Professor Kamlesh Khunti, professor of primary care diabetes and vascular medicine at the University of Leicester.
The researchers conducted a systematic review and meta-analysis of studies into the effects of intake of fruit and vegetables on incidence of type-2 diabetes.
They found that greater intake of green leafy vegetables was associated with a 14% reduction in risk of type-2 diabetes.
The researchers said the results supported the growing body of evidence that lifestyle modification is an important factor in the prevention of type-2 diabetes.
'The potential for tailored advice on increasing intake of green leafy vegetables to reduce the risk of type-2 diabetes should be investigated further,' they concluded.