Here's the message I've been given, maybe it's changed without my noticing but I think it's remained consistent -

balance means giving each variable in an equation similar weight. Eating only one or two food groups is not optimal for health.

Moderation - not eating more calories than you burn throughout the day.

edit - I agree with you about the ever rotating axis of nutritional evil. It's BS. I think part of the reason we go through it though is people ignoring the basic advice I mentioned earlier that's held for so long. Why eat broccoli when I can eat McDonalds? Exercise is hard. ETC