Junk food epidemic

Michelle Obama wanted to expand access to fresh, healthful food; Walmart wanted to expand into urban markets. When the First Lady and the retail giant got together last year to try to eliminate food deserts—low-income areas where there’s nowhere to buy fresh produce—many hoped this effort would put a dent in obesity and other public-health problems.

But recent studies have found little connection between food deserts and obesity. Whatever benefits a supermarket provides, improving people’s diet doesn’t seem to be among them. After all, even supermarkets offer more junk than healthful food—and the junk is more convenient, alluring and affordable.

Making healthful food available isn’t enough. People need to acquire the habit of eating well. Such habits are learned in families and communities. Forming good habits involves fighting unhealthful traditions (as Mississippi pastor Michael Minor is doing in banning fried chicken at church meals) and  reconnecting to the land (see "Eating in ignorance"), as in projects that help children from low-income families grow vegetables. (This is an area in which Mrs. Obama has provided leadership.)