Kudos to The Post’s Eli Saslow for a vivid story in Sunday’s paper about the burgeoning federal Supplemental Nutrition Assistance Program (SNAP) and its impact on struggling Woonsocket, R.I. Because of the 2008-09 recession and new eligibility rules, SNAP enrollment has expanded to 47 million people, including a third of Woonsocket’s 40,000 residents. SNAP’s total cost in 2012 was $78 billion, triple the 2003 level.

I read Saslow’s story with mixed feelings: pride in a generous nation that spends such sums to fight hunger; shame that economic conditions make it necessary to do so; and worry about the long-term consequences of dependency on SNAP.

What really caught my attention, though, were the photographs that showed what some SNAP recipients bought with their government-funded debit cards: Cheetos Puffs, a one-ounce handful of which contains 10 grams of fat; a box containing two dozen 12-ounce cans of Fanta Orange soda, each of which contains 44 grams of sugar; a carton of six-ounceCapri Sun drink pouches, each of which contains 16 grams of sugar.

In short, this immense nutrition program pays for a lot of stuff that is the opposite of nutritious.

I don’t blame the consumers, in the sense that their choices are entirely permissible under SNAP’s rules.

As the Agriculture Departmentexplains on its Web site, federal law “defines eligible food as any food or food product for home consumption” and excludes only “alcoholic beverages, tobacco products, hot food and any food sold for on-premises consumption,” as well as “pet foods, soaps, paper products, medicines and vitamins, household supplies, grooming items, and cosmetics.”

“Soft drinks, candy, cookies, snack crackers, and ice cream are food items and are therefore eligible items,” the USDA notes.

I blame Congress for not updating SNAP to reflect nutritional common sense — and the terrible epidemics of obesity, hypertension and diabetes, which disproportionately affect low-income Americans but increase the entire country’s health-care bill.

The Physicians Committee for Responsible Medicine, a D.C.-based nonprofit, has proposed limiting SNAP purchases to whole grains; fresh, frozen or low-sodium canned vegetables; beans; and fruits. This meal plan would supply 65 percent less fat than the average American diet and twice the fiber, according to the committee.

No doubt such limitations would entail a change in habits for many SNAP recipients — perhaps too much change. Fish and poultry, as well as lean red meat, should probably be included. But even if SNAP paid only for healthy stuff, recipients would still be free to use their own cash for other products. The point is to increase the amount of real nutrition per taxpayer dollar.

The counterargument is that it’s not fair to restrict poor people’s grocery choices. You hear this a lot from the food and beverage industry, for which SNAP has grown into a significant subsidy.

Sorry, I don’t get it — morally or pragmatically. Of course the federal government should be able to leverage its purchasing power for socially beneficial purposes. If you take Uncle Sam’s help, you play by his rules. I repeat: This is a nutrition program, or so the taxpayers who fund it are told. It should nourish.

Probably the most cynical argument against banning junk food from SNAP is that it would “stigmatize” the poor by making them conspicuous at the grocery store. Since when is it humiliating to take only healthful food through a checkout line? And why should this theoretical threat to psychological health outweigh more plausible threats to physical health? Saslow’s story suggests that it’s already no big secret who’s on SNAP in places such as Woonsocket.

At the very least, SNAP should bar sodas, a nutritionally empty “food” if ever there were one. Before he tried to ban large sodas at movie theaters, New York Mayor Michael Bloomberg asked the USDA to authorize a two-year no-soda experiment in his city’s SNAP program.

The department turned him down, echoing food-industry claims that the one-city test would be “too large and complex.” What a threadbare excuse. This is the age of data-mining, scanners, bar codes and debit cards. If SNAP can weed out beer, it can weed out Coke. The Women, Infants and Children (WIC) program limits purchases to a finite list of healthful foods, without unmanageable hassles.

The USDA rejected Bloomberg’s idea in August 2011, while President Obama was in his first term — and first lady Michele Obama was admirably promoting nutrition and physical activity. Maybe in a second term the Obamas will persuade Congress and the USDA to get with her program.

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