Even though you might not be noticing it now, a lack of nutrients in your diet can cause problems on the long term. For example, if your diet contains little minerals and what you eat has a lot of phytic acids (like in grains and nuts) which make it even harder for your body to pick up those minerals, then this is a recipe for problems with yout teeth and bone structure. Your body will draw its minerals from your own teeth in times of shortage, causing all kinds of problems. Not to scare you, but definitely the health incentive should be there. Since you would like to stay healthy in years to come also, right? ;)
Apart from that, maybe you can try and find out why you need so much of an incentive to pick up more healthy habits? For me, sports is among the most fun things I do in the week. We have an Ultimate Frisbee team here in Rotterdam and I just love playing with them!! Find yourself a sport you like, and cool people to do it with! And for food - making quality food is so much fun! Not a punishment ;). And not only making it is fun, eating it is delicious, and even though you feel healthy I am sure that home cooking with quality ingredients will add to your feeling of satisfaction and well-being. So that's a long reply, I know you didn't ask m eanything ;). But wishing you the best, and @kingst thanks for a great post!!