When you watch his videos on Youtube, he recognises that he eats very badly and doesn't even seem to care about it, even if he is a pro runner now. for example in the video "training as a professional runner in Seattle" where he's openly eating junk food.
In one of his videos he even implied that food doesn't really matter and doesn't even consider to diet.
However I've got doubts about it... It seems like he underestimates the whole thing.... What do you guys think?