Diet soda gives you a sugar rush far stronger than the granulated stuff in a sugar bowl ever could - and for no calories. But research is mounting that low-and no-calorie sweeteners may not be great choices for dieters. A recent study found that over nine years, diet-soda drinkers gained nearly triple the abdominal fat-3 in. (8 cm)-as those who didn't drink diet soda. Though scientists are still puzzling over how this may happen, here's what they think is going on. The most popular artificial sweetener in diet drinks ... is about 200 times sweeter than sugar without triggering a feeling of satiety. Bad things can happen when you strip sweetness of its power to satisfy: the link between eating and the role of calories in your body starts to crumble. It may also mess with your [digestive] microbes, [and] be bad for your heart. In a study based on dietary questionnaires of 9,500 people, those who said they drank one can of diet soda a day had a 34% higher risk of metabolic syndrome - a cluster of risk factors that can lead to heart disease and Type 2 diabetes - than those who didn't drink diet soda. The study stopped short of drawing a cause-and-effect link, but the association surprised the authors, who called for more research.