Nuts
Nuts such as walnuts, almonds, hazelnuts, and pecans are a good source of L-arginine which gets converted into nitric oxide. Walnuts also contain a plant-based omega 3 fat that's necessary for a healthy cardiovascular system. Add a few to your morning oatmeal, add them to salads, or have a handful as an afternoon snack. Looking for a sweet treat? Try these truffles sweetened with raisins.
[Photo via @velvetfog09]