IN 2010, the U.S. Department of Agriculture distributed $65 billion worth of food-stamp aid to 46 million needy Americans. Now wouldn't it be nice if more of that Supplemental Nutrition Assistance Program money was used for buying fruits and vegetables, and less for chips and soft drinks?

It's a big problem. According to the National Food Consumption Survey, SNAP users eat less produce and buy 40 percent more sugary beverages than any other group of Americans. A 2010 Harvard study in California found obesity rates were 30 percent higher among food-stamp recipients than others. By one estimate, for every year a person receives SNAP aid, his or her body mass index (an indicator of overall body fat) rises 1.6 points.

Part of the problem is access: Inner-city food-stamp recipients have more access to junk-food-laden mini-marts than full-scale grocery stores or farmers markets. Another is cost: Produce may seem less filling and costs more than, say, a 99-cent box of macaroni and cheese. But a third part of the problem comes courtesy of Washington: Powerful lobbying by Big Food, including the beverage, corn, and sugar industries, keeps the USDA from prohibiting or even discouraging use of SNAP funds for junk food. Advocates' complaint that blacklisting certain foods is "paternalistic" adds to the problem.

For example, New York City had proposed a two-year experiment to see if obesity among SNAP recipients could be reduced by barring the purchase of soda with food stamps. The USDA turned that proposal down, saying that it preferred "incentive-based solutions." The agency even limits education programs: An article in the American Journal of Public Health notes that the USDA bans "nutrition education messages which convey negative messages or disparage specific foods, beverages, or commodities."

If even presenting scientific evidence on the link between, for example, soft drinks and obesity (and the diseases such as diabetes and hypertension that result) is verboten, what can be done? The answer may be emerging from the ground up, via a grass-roots movement that links SNAP users with local farmers markets. It's a trend that already touches Fredericksburg.

Since 2004, when scrip-type food stamps were replaced by Electronic Benefit Transfer cards, SNAP recipients have been locked out of cash-only farmers markets, which often operate in places without electricity or phones. EBT cards, like debit and credit cards, require an Internet connection.