Christopher McDougall's "Born to Run" offers some interesting vindication for veg(etari)ans.

[eppur_se_muova]

http://www.powells.com/biblio?show=hardcover:sale:9780307266309:17.46

Ch. 25, I believe, is the chapter in which he discusses diet and how it affects health. Describes ultra-endurance runners propelled by pure veggie diets.

Ch. 27 eviscerates Nike and its "high-tech" approach to running shoes.

Ch. 28 discusses why some scientists -- from anthropologists to biomechanicists -- argue that humans evolved to run long distances, more so than any other creature on Earth. Really fascinating reading.

This is NOT a book just for runners, or even just for athletes or health fanatics. McDougall is a very engaging writer and really draws you into the framing story -- an "ultimate showdown" between some of the best ultrarunners in the world -- but the intercalated background is fascinating reading in its own right.