I eat OK (I tend to cook chillis and currys using sauces, a couple vegetables/pulsars and meat), however I exercise at least 3 times a week (games of football [soccer], run, squash, climbing etc). I also drink a few pints of water or cordial a day. Recently I've been cutting down on my sugars in the hope of slightly more sustained energy levels and it does seem to have had a small effect. Although I'm still only 20 and have a fast metabolism the only thing that really scares me is saturated fat, because I can't really exercise it away. Otherwise as long as you're reasonable (not eating fast-food all the time) I don't see it being a huge problem.