The calories in the drink could make you obese and increase your risk of type 2 diabetes and heart disease while those in starch won't have any harmful effect at all, say researchers from the University of California at Davis.
The drinks can still cause health problems even if you don't put on any weight drinking them, and new warnings on bottles and cans are fully justified.
In fact, sugar-sweetened drinks are "uniquely harmful to human health" and aren't merely the source of yet another calorie, the 22 nutritionists concluded, echoing the verdict of a US court that had been asked to adjudicate on the warning labels.
The researchers also confirmed that eating polyunsaturated fats, such as vegetable oils, seeds and nuts, lowers the risk of diseases such as heart problems. "We all agree that a healthy diet consisting of minimally-processed whole grains, fruit, vegetables and healthy fats promotes health compared with the refined typical Western diet," said lead researcher Kimber Stanhope.
The idea that all calories are equal was aggressively promoted by the sugar industry in the 1950s when its products were coming under close scrutiny. They won the day, and attention eventually focused on high-fat foods instead.