If you run, don’t run to lose weight.
Run to run, for the achievement, and yes, the enjoyment of it. The health benefits will follow.
If you run in order to lose weight, you may actually end up underfeeding yourself – and then, you’ll exhaust yourself, maybe even get sick. I may possibly be speaking from personal experience.
My advice: just make sure the calories you do consume are calories that will fuel you well. Make them count. Eat more protein and veggies – not because it’s “health food,” but because that kind of food fuels a running body. Drink lots of water.
And go ahead, have a big fatty cheeseburger every once in awhile. It won’t kill ya.