WASHINGTON — The political clash over climate change has entered new territory that does not involve a massive oil pipeline or a subsidy for renewable energy, but a quaint federal chart that tries to nudge Americans toward a healthy diet.

The food pyramid, that three-decade-old backbone of grade-school nutrition lessons, has become a test case of how far the Obama administration is willing to push in pursuit of its global warming agenda.

The unexpected debate began with a suggestion by a prominent panel of government scientists: The food pyramid – recently refashioned in the shape of a dinner plate – could be reworked to consider the heavy carbon impact of raising animals for meat, they said. A growing body of research has found that meat animals, and cows, in particular, with their belching of greenhouse gases, trampling of the landscape and need for massive amounts of water, are a major factor in global warming.

Cattle industry representatives quickly raised the alarm, summoning help from Republicans in Congress and their allies.

“There is an anti-meat agenda out there, and this is a way to go after meat,” said Daren Bakst, a fellow at the Heritage Foundation, the conservative research and advocacy organization. “We need to just focus on nutrition. Once you bring up these other things, it undermines the legitimacy of the guidelines.”

Administration officials are already enmeshed in bitter fights with Republicans over coal-fired power plants, methane emissions from oil and gas production, and regulation of automobiles. Whether they have the stomach for adding a food fight to the list remains uncertain. But the possibility that climate-change politics could affect nutrition guidelines serves as a reminder of how many parts of daily life the struggle to limit global warming can reach.

“We can’t solve the climate problem with just what we are doing with fossil fuels and energy,” said Doug Boucher, director of climate research at the Union of Concerned Scientists, which is lobbying for changing the pyramid. “Food is a big part of it.”

The food pyramid is just the latest function of government where climate change looms large after years of not being a consideration.

Legions of military officers are focused on shifting the nation’s fighting force to clean energy, hoping ultimately to not only limit global warming, but also save money and reduce the need for huge, vulnerable oil supply lines. The Department of Housing and Urban Development is pushing a green building portfolio. Even the Department of Education is required to regularly produce a climate-change action plan.

But the stakes are high when it comes to steak. The dietary guidelines embodied in the pyramid are the core of the nation’s food policy. And although the nation’s obesity epidemic raises questions about how much the guidelines affect public behavior, they do shape billions of dollars of government programs, including school lunches and food stamps.

Environmental and animal rights groups see the discussion of the role food plays in climate change as an opportunity to reach a vast new group of Americans.

“People care a lot more about their own personal health than they do about the environment or animal welfare,” said Michael Jacobson, executive director at the Center for Science in the Public Interest in Washington. “So these groups are hoping to make progress on their issues by linking them to healthier diets.”

A revamp of the food pyramid to take climate into account would be a bold step. Despite a major push by the United Nations for countries to rework dietary policies with an eye on climate impact, none has. The Netherlands is expected to be the first when it releases a new chart illustrating food guidelines this year, said Kate Clancy, a longtime sustainability advocate who advised the federal panel.

“This is a way to get people to think about how their food is produced,” Clancy said. “We should not be making it seem like there is no connection between what you eat and its impact on the planet.”

Hoping to nudge governments, advocacy groups have been busily designing mock-ups of what a revamped food pyramid would look like. A rendering by the Italy-based Barilla Center for Food and Nutrition has the traditional pyramid alongside an upside down “Environmental Pyramid.”

Beef ranks as the least healthy and least environmentally sound food on both charts. Cookies, however, are unhealthy for your body, but not necessarily the planet.

Differences like that provide talking points for critics of a sustainability-focused pyramid. Nutritional guidance, they say, is already confusing enough for consumers.

“It is becoming harder and harder for the public to figure out what the scientists are saying with this document,” said Marshall Matz, an attorney who was chief counsel to the Senate Agriculture Committee when it wrote the nation’s first dietary guidelines in the late 1970s. “If we integrate all this new information into it, I fear it will be useful for about 5,000 Ph.D.s and be of no value to the average American consumer.”