Choosing what we eat is learned behavior. We, to some degree, learned what to eat from our parents, and they from there's. We then modified that due to cost and availability, like and dislike, all without thinking about it.
At the same time, those food changed, wheat became chemically fertilized, carbohydrate portion grew faster that the protein portion. New cultivars came along. Cheaper process add more sugar, and oils, and transfats.
All we need to do is go back in time, eat only what our ancestors ate, and the problem should self-correct. No sugars of any kinds, no grains, animal feed, no manufactured oils. Enough fat to keep hunger at bay, low enough carbs to keep insulin low, so that lipogenesis can occur, and the problem should go away.
The problem with O6 is two fold, one high calories, and two, it amplifies the insulin release for any defined amount of carbohydrate. (ref http://thatpaleoguy.blogspot.com/2011/09/follow-money-iii.html and his previous post and elsewhere)