Flavonoids help the body regulate sugar levels (glucose) and have been praised for protecting against heart disease, some cancers and dementia too.

Researchers from the University of East Anglia and Kings College London found that high intakes of anthocyanins (present in strawberries, blackcurrants, blackberries and blueberries) can be linked with lower insulin resistance and better blood glucose regulation. They also lowered inflammation.

Results from the study were published in the Journal of Nutrition and involved 2,000 women keeping a diary of all the food and drink they consumed with their blood samples being analysed.

"Small changes to the normal diet you have can have significant effects on prevention efforts. We show that one portion of berries every day can help you control your blood sugar levels but also prevent you having a heart attack," said Professor Aedin Cassidy from the University of East Anglia, reports Sky News.

"This is one of the first large-scale human studies to look at how these powerful bioactive compounds might reduce the risk of diabetes. Laboratory studies have shown these types of foods might modulate blood glucose regulation - affecting the risk of type 2 diabetes.

"But until now little has been know about how habitual intakes might affect insulin resistance, blood glucose regulation and inflammation in humans."

This is by no means a free pass for a chocolate and red wine binge though. Overindulging on these luxuries can result in the negatives outweighing the positives, so like everything else, consume them in small portions - everything in moderation.

It's important to remember that a healthy diet and regular exercise are also contributing factors to the prevention of type 2 diabetes.

A separate study has also found that Chinese herbal medicine can slow down the development of type 2 diabetes.

A clinical trial, led by the University of Chicago, found that the herbs were actually similar to medical prescriptions for controlling pre-diabetes, which is often referred to as the grey area between normal blood sugar and diabetic levels.

People with pre-diabetes have a significant risk of it developing into type 2 diabetes.

"With diabetes evolving into a serious public health burden worldwide, it is crucial to take steps to stem the flood of cases. Patients often struggle to make the necessary lifestyle changes to control blood sugar levels, and current medications have limitations and can have adverse gastrointestinal side effects," explained Doctor Chun-Su Yuan, one of the study's authors, reports British newspaper The Daily Mail.

The trial involved the 389 recipients taking part randomly being selected to take either a capsule containing ten Chinese medicines (Tianqi) or a placebo over the course of a year.

Out of those who took Tianqi, 36 developed diabetes, compared to 56 in the placebo group.

The results suggested that taking Tianqi reduced the risk of diabetes by 32.1 per cent.

"Traditional Chinese herbs may offer a new option for managing blood sugar levels, either alone or in combination with other treatments," added Doctor Yuan.