Link between falling minimum wage, cheap food & obesity

From the National Bureau of Economic Resesarch:

Growing consumption of increasingly less expensive food, and especially “fast food”, has been cited as a potential cause of increasing rate of obesity in the United States over the past several decades. Because the real minimum wage in the United States has declined by as much as half over 1968-2007 and because minimum wage labor is a major contributor to the cost of food away from home we hypothesized that changes in the minimum wage would be associated with changes in bodyweight over this period. To examine this, we use data from the Behavioral Risk Factor Surveillance System from 1984-2006 to test whether variation in the real minimum wage was associated with changes in body mass index (BMI).

From Grist.org article & the study:

[E]ven though lower income persons are more likely than higher income persons to be obese, obesity has increased most among higher income persons in recent years, as might be expected if changes in the price of food away from home were driving increases in obesity.

You know, how fast food has gotten cheaper relative to making your own lunch/dinner with healthy food at home, eating out more often piles on the weight more easily.