Sunday, October 12, 2003
Today's New York Times Magazine leads with an article blaming the obesity epidemic on a shift in US agricultural policy in the early 1970s to one that encourages overproduction (as opposed to the New Deal policy that fought overproduction.) Terms like "overproduction" and "underproduction" are employed in a rather blithe manner throughout the article, and there are many assertions that at least this economist finds doubtful ("The rules of classical economics just don't seem to operate very well on the farm"). Nevertheless, gluttony is a growth vice right now, and there is a good deal of discussion about policy initiatives aimed at reducing obesity.
One problem with the Times Magazine article is that obesity has been increasing for a century or more, not only since the 1970s. Second, perhaps the major influence on American obesity has not been cheaper food, but more sedentary lifestyles. According to this NBER working paper by Darius Lakdawalla and Tomas Philipson, about 40 percent of increased obesity (since the mid-1970s) can be traced to technological innovations in agriculture, with 60 percent associated with lifestyle changes. In another NBER working paper, Philipson and Richard A. Posner have argued that behavioral feedbacks might render increases in obesity to be self-limiting. And by and large, the tremendous increase in agricultural productivity in the past 50 years has been extremely beneficial to people worldwide.
Cheaper food for the masses, however, no doubt does play a role in increased obesity. The Times article starts off with another vice example, that of cheap whiskey in the early 1800s in the US. Per capita consumption of alcohol surged, peaking in approximately 1830, at levels some three times higher than today. The gin epidemic in Britain in the early 18th Century is another instance where increased availability (via lower prices) of alcohol led to significant problems.
More generally, heightened availability of a drug (distilled alcohol) or other vice-related commodity, in a community that has not yet "socialized" the vice, has often brought with it severe costs. Cheap, well-marketed and palate pleasing calories undoubtedly have
contributed to increased obesity. As with drugs, however, we need to inquire about the "rationality" of decisions to consume extra calories. For public policy, I maintain once again, the goal should be to offer some assistance to those who have significant self-control problems, without imposing significant costs on those whose eating and exercise decisions are "fully rational." Banning fatty foods does not meet this test, though marketing controls or even some targeted taxes might.