Starting two years ago, I did a "NOvember":
No Wheat
No sugar (or honey, or maple syrup)
No alcohol
No fried foods
30 days.
This is my third year (though last year it ended 10 days early because the whole family got the stomach flu, and I lived on saltines and plain pasta).
Anyway, so far so good. I was cleaning up the kids' mac and cheese and unthinkingly ate off the spoon. Ah well, one bite.