It depends on if you want to get high or not. Leaves have a high CBD, and hardly any thc. If you use a medible with only leaves, it will help you sleep at night, Restless leg syndrome, and ADD, but you won't feel any psychoactive effects, as mentioned above. You can juice fresh leaves which has benefits as well. Leaves have benefits, they just arenn't desired by everyone.
We use the whole plants in our stuff (Root 66) and I, roots and all.
Peace
Eek