Marc Ambinder has some interesting pieces up at the Atlantic on the First Lady’s efforts to combat childhood obesity. I obviously have a lot to say on that but am short on time. In the mean time I will point you to Robert Lustig’s Nature article on childhood obesity, which was a watershed for me personally.
The article is a bit dense for those without a science background, nonetheless, it is extremely valuable. I recommend opening Lustig in one window and Wikipedia in another and just making the hard slog.
Here is the abstract
Childhood obesity has become epidemic over the past 30 years. The First Law of Thermodynamics is routinely interpreted to imply that weight gain is secondary to increased caloric intake and/or decreased energy expenditure, two behaviors that have been documented during this interval; nonetheless, lifestyle interventions are notoriously ineffective at promoting weight loss. Obesity is characterized by hyperinsulinemia. Although hyperinsulinemia is usually thought to be secondary to obesity, it can instead be primary, due to autonomic dysfunction. Obesity is also a state of leptin resistance, in which defective leptin signal transduction promotes excess energy intake, to maintain normal energy expenditure. Insulin and leptin share a common central signaling pathway, and it seems that insulin functions as an endogenous leptin antagonist. Suppressing insulin ameliorates leptin resistance, with ensuing reduction of caloric intake, increased spontaneous activity, and improved quality of life. Hyperinsulinemia also interferes with dopamine clearance in the ventral tegmental area and nucleus accumbens, promoting increased food reward. Accordingly, the First Law of Thermodynamics can be reinterpreted, such that the behaviors of increased caloric intake and decreased energy expenditure are secondary to obligate weight gain. This weight gain is driven by the hyperinsulinemic state, through three mechanisms: energy partitioning into adipose tissue; interference with leptin signal transduction; and interference with extinction of the hedonic response to food.
I don’t agree with all of Lustig’s conclusions as written in the article. This is in part because the accurate answer to some of the questions is: “I really have no idea and neither does anyone else.” Yet, that’s hard to get published.