Hi there,
I just wanted to clarify that the guy who wrote freakanomics is the gentleman who was on the morning show, and is not the same guy who did the research. The original paper is 63 pages long and the section on diet is very interesting. His name is Seth Roberts and he is a psychologist at UC Berkeley. His research is posted on the Berkley website.
THe interesting point he looks at that I've never seen anyone deal with before, is Set Point: the weight at which our bodies are most comfortable. What he found was that the fructose and water actually allows the set point to adjust as one loses weight, which is different than any findings he's ever found before, and this is how he expains his ability to keep off his weight, along with the other people who've tried and lossed and kept the weight off.
In his research he looks at Cravings, weight loss maintanance, over eating and set point. It's more thorough than indicated on the morning show piece or in what freakanomics covers. I suggest plugging through the actual research before making a decision about this theory either way.
take care
Tracy