In 2005, the average American consumed 64kg of added sugar, a sizeable proportion of which came through drinking soft drinks. Now, in a 10-week study, Peter Havel and colleagues, at the University of California at Davis, Davis, have provided evidence that human consumption of fructose-sweetened but not glucose-sweetened beverages can adversely affect both sensitivity to the hormone insulin and how the body handles fats, creating medical conditions that increase susceptibility to heart attack and stroke.