Nuts are a great source of protein and omega-3 fatty acids and can help suppress your appetite. The lowest-calorie nuts are almonds, cashews, and pistachios. Choose dry or raw roasted nuts; avoid those that have been packaged or roasted in oil. These oils have unhealthy fats and require high temperatures that destroy nutrients.
Omega-3 EFAs support a healthy brain, and magnesium helps you feel calm and relax. If you're feeling down, try supplements with these minerals as well as Vitamin D, as deficiencies in these areas have shown links to feelings of depression.