Exercise (activity in any form you can think of, cardio preferably within the first 3 hours of waking for the day) and lots of fresh fruit and/or fruit juices (when 100% and not from concentrate) also dark green vegetables, and throw in a small but consistent amount of nuts, almonds, walnuts, filbers. That about sums a good core of a healthy lifestyle. I have dabbled much in diets the last 5 years. Avoid as much fake sugars as possible (Splenda/Sucralose, Sorbitol, Maltitol), don't avoid carbohydrates like Atkins suggests, rather be smart about how much & when you consume pastas, breads, etc... As much as some replacement ingredients may be okay for the body, they screw the body up more often than not, as we have evolved with our bodies expecting naturally occuring sugars, grains, organicly grown plants. Don't eat the last 3 hours before you lie down for the night. It really is becoming so much more clear to me the last month or two as I have followed this path more strictly (without deviating and my body has never felt better since age 22 - when I didn't have to worry about anything I ate, or so it seemed at the time). I am 32 now and this is the field I have been studying on a leisurely basis the last 6 months. Oh yeah, I also subscribe to New Scientist magazine, excellent publication (online edition included), a college student discount is available if you check a box
I would also like to recommend a magazine called OnFitness, good stuff. By the way Lashiec, perfect use of the inline image mod.