One of my least favorite words in this language of ours is healthful. I was about to write a diatribe against it when I came across this page which explains that the recent increase in the use of this hideous word is actually a return to the proper use. I still don't like it: almost every time I hear it used, the context is politically correct/sterile/manipulative. I put it in the same category as going forward, impact used as a verb and proactive. Unfortunately, in this instance I am beat; healthful is proper English.
The linked page also has some other interesting language tidbits, though most of them are already pet peeves of mine. One, however, was new to me: apparently the word prevalent was originally used pejoratively. So, "happiness is a prevalent emotion" is somewhat contradictory (unless you don't like happiness). "Cockroaches are prevalent in Chicago" would be a more appropriate use.
