While I think there is something to be said for eating more protein, there is also A LOT to be said about the meat industry and how unhealthy and unnatural it has become to the point where most cows are fed corn or even cow rather than allowed to graze. They are given enough antibiotics to cause many antibiotic resistant strains of bacteria. This isn't even taking into consideration that some of the meat is from cloned animals. Watch Food Inc. if you want learn what's really going on in the meat industry, then come back and tell me how safe you feel existing on a diet that is meat based.
It's gotten to the point where, if you are educated about what is going on in the food industry, you'd almost prefer not to eat at all as it starts to feel like the safest choice.