Cholesterol-lowering drugs may be linked to an increased risk of diabetes, according to a new study of middle-aged and older women.

For their report, Dr Yunsheng Ma of the University of Massachusetts Medical School in Worchester and his colleagues used data from the Women's Health Initiative, including more than 150,000 diabetes-free women in their 50s, 60s and 70s.

But researchers say that shouldn't dissuade people with heart disease - or at risk of it - from taking so-called statins.

Instead, statin users should try to reduce their risk of diabetes in other ways, such as by losing weight, and should have their blood sugar regularly monitored, they say.

"The conclusion still stands that overall, those people who've got existing heart disease or have had previous strokes, they still would get vast benefits from statins", as would those at high risk for heart disease, says Naveed Sattar, a metabolism and diabetes researcher at the University of Glasgow, in the UK.

Instead, the finding "may make us a bit more cautious about putting statins in the water, for example," Sattar, who wasn't involved in the new study, says.

In other words, not all people with few heart risks should be taking the drugs, as some researchers have suggested, because they aren't side effect-free.