Some foods are associated with better happiness, as certain nutrients help the brain and body function in ways that support mood regulation. A balanced, varied diet including these foods may support mood over time, but no single food can prevent or treat depression or anxiety. Dark ChocolateM-Production / Getty ImagesRegularly eating small amounts of dark chocolate may support mood in some people. What to Keep in MindThese foods may support mood, but they are not a substitute for mental health treatment. Eating a varied, balanced diet that includes these foods may support emotional well-being over time.