“Consider the recent uncontrolled experiment in which approximately 200 million adults in the United States have been encouraged to consume higher levels of dietary carbohydrate in place of fat. In the same time frame, more than half of us have ended up overweight or obese. The results from this national level experience point us to the logical conclusion that the ability to remain healthy with increasing levels of carbohydrate is limited to a subset of the population. Therefore determining who those people are and what characteristics give them the ability to consume carbohydrate without untoward effects is a major question that can and should be addressed.”