This one may seem like a holy grail for carb lovers, but it’s true: carbohydrates actually stimulate mood-boosting chemicals in the brain. Carbs promote the production of serotonin, the feel-good brain chemical. Low-carb diets, on the other hand, have been known to cause high levels of anger, tension, and distress. A study that followed people on a low-carbohydrate diet for one year found that those people experienced more depression and anxiety than those on higher- carbohydrate diets. In addition, most whole grains contain fiber, which is good for the heart and the digestive system. So, when that afternoon slump hits, try some healthy, whole-grain/wholefood carbs to get yourself feeling better.