I wanted to clarify that I am not attacking the “carbs are bad” idea per se. Personally, I’m agnostic. What I was trying to do in my previous posts was to point out that the question is a quantitative one and cannot be settled by a qualitative examination of the underlying physiology. Gary Taubes would be the first to agree and he is actively working towards testing his hypothesis experimentally. I also wanted to point out that single experiments are not definitive. The recent JAMA paper suggests that low carb diets speed up metabolism relative to low fat diets but like many clinical experiments, the effect could have been due to a statistical anomaly or systematic error. As I have posted previously in the past (e.g. see here), clinical and epidemiological results are as likely to be wrong (if not more) as correct. Unlike mathematics, where a theorem is either wrong or right, clinical and epidemiological results are more like imperfect snapshots of the truth. It will only be through a long process of accumulating evidence will the answer be revealed.