I've watched Dr. Lustig's video previously, and in general its the same principles touted by Gary Taubes, but I still find it dubious. You can look at your patient population and come up with a hypothesis that would make sense from a pure biochemistry perspective, but that's really no different than what the proponents of dietary fat as a cause of heart disease did.

And since when is monitoring people in a controlled lab for a few weeks at a time (likely limiting their physical activity and who knows what kind of stress to the system having your blood drawn every 30 minutes induces) considered valid scientific research when it in no way exemplifies real world situations that people are exposed to. And sugar is apparently carcinogenic because it can cause an increase in baseline insulin levels as a response, which can drive glucose into potential tumor cells allowing them to grow. That's purely speculative, and very difficult to substantiate when there are so many other reasons for people to develop cancer: http://www.nytimes.com/2012/03/13/health/research/red-meat-l...

Personally, I'm still convinced that a calorie is a calorie. And the reason we've been gaining weight, with greater incidence of heart disease, diabetes, etc. is that we simply consume too much food, perhaps too much processed food, but in general we just eat too much. So eat less, and the best way is to consume small portions of food multiple times a day instead of large meals with large gaps in between. Trust me, it works.