When it comes to losing weight, eating healthy has a much bigger impact than spending time at the gym. As this video from Vox explains, weight loss is more complicated than just calories in versus calories out. Plus we burn the most calories doing routine things (like breathing and digesting food), not sweating it out at the gym. This isn’t to say you shouldn’t work out—regular exercise comes with tons of health benefits—but don’t expect more gym time to always lead to weight loss.