+1 So far, from what I have seen, substitutes do more harm than good and synthetic foods/additives should be avoided. I think everything in moderation should be the healthiest eating habits unless someone has specific health issues.
Healthy Heart Diet = If it tastes good, spit it out.
More seriously, I agree with Indylan, you are better off with smaller amounts of the real thing than larger amounts os substitutes.
The real thing is usually a healthy food if eaten in moderation. Substitutes may be low in certain "harmful" ingredients but their ingredient list usually reads like a hazmat site description.