My advice here is pretty basic. We all know what is good for you and what isn’t. There is nothing in my diet that is off limits, I don’t shun wine, chocolate, or the occasional french fry. But, I fuel myself on much healthier things and so my overall diet is pretty healthy. I focus on making sure I am getting plenty of vegetables, fruit, complex carbs, and lean proteins. If I have had toast with peanut butter for breakfast, a recovery shake after a workout, a big salad with lots of toppings for lunch, yogurt and trail mix for a snack, and a stir fry filled with veggies for dinner, than I don’t feel guilty if I have a bowl of ice cream or a chocolate bar before bed. I do have the occasional day where I don’t eat the healthiest, but I don’t let myself feel guilty. No one is perfect all of the time. As you train you learn foods that make you feel better and foods that don’t. Don’t think you must have a strict diet to be a runner, focus on the good stuff and you’ll be just fine.