Fructose: I try to stay away at all costs when cutting, as it restores liver glycogen rather than glycogen found in muscles. For general health, fruit is good, but for bodybuilding, not so much.
Dairy: Most dairy products will illicit an insulin spike that i don't necessarily want on a cut, but not such a big deal to me when bulking. I always keep the good ole cottage cheese in the lineup though...
Sugar substitutes: If it's found that Splenda is some type of carcinogen, i'm royally fucked. However, the sucralose in splenda appears to be the safest one out there.