Scientists at the Erasmus Medical Centre in the Netherlands analysed data from 9,535 patients over the age of 45 prescribed statins.
Professor Bruno Stricker and colleagues tracked each of the participants for up to 15 years, to assess if the drugs are linked to a higher risk of type 2 diabetes.
Patients on statins had higher blood glucose levels of insulin and showed more signs of insulin resistance - a key cause of diabetes and heart disease.
And the researchers found patients who had ever used statins had around a 38 per cent higher risk of developing type 2 diabetes.
They said the risk was even higher in patients who were overweight or obese, which is a known driver of the condition.