The other issue is many people assume they can drown a Big Mac with a diet soda and not gain weight. They feel they’re doing their body a favor by not consuming traditional, high-calorie soda. That’s not the case. The calories from the hamburger and French fries remain, leading to weight gain if consumed regularly. Despite the inconsistent link between weight gain and diet sodas, there is still cause for concern. Sharon Fowler, MPH, who led a similar San Antonio study had this to say about artificial sweeteners, “I’m not convinced these sweeteners are as safe as they should be, given their widespread use, I’m concerned we’re in the middle of a giant experiment.” Until we know for sure, it might be best to avoid diet soda altogether. You don’t want to end up like the oversized rats in this study, so it might be better to just chug those eight glasses of water and leave the soda alone.