I've written many times on here that a high carbohydrate diet can wreck havoc on the system, particularly when those carbs are of the grain and fructose variety. But hey, I'm just a coach. But here it is coming from an MD's mouth.
Not that I think MD's are the end-all-be-all of health knowledge, I know too many after all. But when it's someone that used to tout the "Fat = Cholesterol" hypothesis now changing his tune, I think that carries a lot of weight.