They may be tasty, resfreshing and, well, smooth… but American researchers now say that smoothies and juices are a new risk to our health because of the amount of sugar the so-called healthy drinks are believed to contain.

Researchers from the UK, USA and Singapore found that, in large-scale studies involving nurses, people who ate whole fruit, especially blueberries, grapes and apples, were less likely to get type 2 diabetes, which is obesity-related, but those who drank fruit juice were at increased risk.

People who swapped their fruit juice for whole fruits three times a week cut their risk by 7 percent.

The study is published in the journal Pediatric Obesity.