New research suggests that Splenda - an artificial sweetener recently considered safe - may contribute to serious health problems like cancer. The study, published in the International Journal of Occupational and Environmental Health, found that mice fed sucralose daily throughout their lives developed leukemia and other blood cancers. In response to the findings, the Center for Science in the Public Interest - a nutrition watchdog group that assesses the safety of food additives - has now formally recommended that consumers avoid the sweetener. That's a big deal, considering that until 2013, they'd rated the additive as "safe." This new evidence was especially powerful because it was funded without special interests in mind, explains Lisa Lefferts, MSPH, senior scientist at the CSPI. "For most food additives, the safety studies are conducted by the manufacturers who have financial incentives," Lefferts says. Even if you discount this new mouse study, you'll still find plenty of reasons to skip out on sucralose. A growing body of research shows that artificial sweeteners may actually cause weight gain, not weight loss. One study found drinking diet soda was linked to increased belly fat; in another, each daily can was associated with a 41% jump in obesity risk. Sucralose has even been shown to mess with your blood sugar and insulin levels, causing spikes and dips that could lead to cravings later on. The bottom line: the scientists at the CSPI firmly believe you should steer clear of sucralose.