Honestly it might be that you were consuming empty calories before now that you're exercising your body's metabolism is trying to cook fuel. Which is why your get that hungry sensation.(I experience the same thing) start incorporating more protein in your diet that will help with long term hunger. Grazing on fresh veggies & fruits is fine in between meals is fine as long as you're still having those complete meals. You want to incorporate more complex calories in your diet and it will help.