Students at Ashlawn Elementary School buying and enjoying their lunches. Parents are pushing for tougher standards on nutrition in school food. (Sarah L. Voisin/The Washington Post)

It was once a staple of public school cafeterias that blended the indulgent and the nutritious, satisfying parents and children both. But chocolate milk is uncontroversial no more. Dozens of districts have demanded reformulations. Others have banned it outright.

At the center of these battles are complex public health calculations: Is it better to remove sugary chocolate flavorings at the risk that many students will skip milk altogether, missing out on crucial calcium and Vitamin D? Or should schools instead make tweaks — less fat, different sweeteners, fewer calories — that might salvage the benefits while minimizing the downside?

However schools answer these questions, protest inevitably follows. When Fairfax County and D.C. schools banned chocolate milk last year from elementary lunch lines, officials heard not just from parents and students. They also received letters and petitions from a slew of nutritionists and influential special interest groups.

Most accused the districts of acting rashly, robbing students of a tasty drink and the vitamins and minerals that fuel bone and muscle growth.

“We got 10 to 20 e-mails a day,” said Penny McConnell, director of food and nutrition services for Fairfax. “It was a lot of pressure.”

This month — and partly because of that pressure — Fairfax officials announced that they would reintroduce chocolate milk in school cafeterias. The newer, low-fat version includes sucrose, which is made from sugar cane or beets, instead of high-fructose corn syrup, which some critics say is more heavily processed and, as a result, less healthy.

Such reformulations have satisfied some of chocolate milk’s critics. But most scientists and nutritionists, including those employed by local school districts, say that changing sweeteners makes little dietary difference if the total calorie content stays the same.

This is a view embraced by the Corn Refiners Association, which often finds itself on the losing side of such changes. “Why should school districts pay more for one sweetener when children’s bodies can’t tell the difference?” said Audrae Erickson, the group’s president.

Several other school districts in the Washington area are changing the formulations of their chocolate milk to switch sweeteners and lessen the amount of fat and sugar. But most are continuing to make it available to students. D.C. schools have resisted the push to restore chocolate milk to their cafeterias.

The stakes are high because more than 70 percent of the milk distributed in school cafeterias is flavored, according to the Milk Processor Education Program, an industry group. Fairfax alone serves 62,000 gallons of chocolate milk a year. And the formulations used in many cafeterias across the country have more calories, ounce for ounce, than Coke.

Such statistics have drawn the attention of those lobbying for healthier school lunches at a time of rising obesity among children. Parents in many districts have been vocal.

“If we want to fix childhood obesity, chocolate milk is just one of the things we need to get rid of,” said Jeff Anderson, a parent of three students at Wolftrap Elementary in Vienna and a member of Real Food for Kids, a Fairfax area advocacy group. “It’s a treat, not something you have every day with lunch.”

Nutritionists, meanwhile, have split between those who think chocoloate milk is worth the payoff in nutrients and those who don’t.

“Trying to get students to consume calcium by drinking chocolate milk is like getting them to eat apples by serving them apple pie,” said Ann Cooper, a leading advocate for healthy school lunches.

The catch is that when schools remove flavored milk, students drink less milk. The milk processors’ group puts the number at 37 percent less milk overall.

Based on such statistics, the National Dairy Council has launched its Raise Your Hand for Chocolate Milk campaign. “Chocolate milk is the most popular milk choice in schools,” according to the campaign’s pitch, “and kids will drink less milk and get fewer nutrients if it’s taken away.”

Sandwiched between concerned parents and vocal industry representatives are school districts such as Fairfax, which must also consider the tastes of their young consumers. In November, when trying to create a chocolate milk formula that satisfied as many parties as possible, the district held a “taste party” at Lane Elementary School in the Alexandria section of Fairfax County.

“Tastes really chocolatey,” one student wrote on the survey distributed to 24 child-testers.

“Really awesome,” wrote another.

Nearly all of the students liked the new milk, but school officials decided it was too much of a good thing. They cut two grams of sugar from the formulation — going from 24 grams per half-pint container to 22 grams — and decided against retesting it.

The new formula, created by Dallas-based Dean Foods, is complete. Fairfax will soon be joined by several other Washington area school districts in introducing the new milk this month.

Dean Foods, one of several chocolate milk suppliers across the country, sells 144 million gallons of chocolate milk in cafeterias across the country. It’s a relatively modest but symbolic part of the company’s sales, said company spokesman Jamaison Schuler. “This is not just a part of our business, it’s a part of our legacy.”

Jostled by the new politics of school lunch, Fairfax officials have vacillated over other staples. This year, for example, they removed salt from pretzels, but weeks later they were coaxed into putting it back.

“All of a sudden, everyone who eats is a nutritionist,” McConnell said. “It makes our job a lot more difficult.”

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