http://garytaubes.com/2011/11/catching-up-on-lost-time-%e2%80%93-the-ancestral-health-symposium-food-reward-palatability-insulin-signaling-and-carbohydrates%e2%80%a6-part-iia

Some interesting discussion in the comments.

I accidentally linked to one of the comments on the post; now I've removed the part that jumps to the comment.  Maybe the link will work better now.