A cow stands in a field by a factory of EL Fouladh, the Tunisian Steel Manufacturing Company which belches smokes as it produces steel billets in Menzel Bourguiba on April 8, 2011.National Journal

Eating less meat is better for the environment.

That's the advice doled out by an independent panel of experts earlier this year in a set of recommendations for the next round of federal dietary guidelines.

But if House Republicans get their way, that message may never be delivered.

A pair of spending bills moving through the House Appropriations Committee contain a provision backed by House Republicans that would limit the dietary guidelines to "matters of diet and nutrient intake"—a requirement that effectively blocks the addition of any warning that eating red meat (therefore encouraging the production of it) can contribute to climate change.

"The Dietary Guidelines Advisory Committee was created to provide science-based comments on the relation of diet and nutrition to American's health, not impose an anti-meat, anti-agriculture agenda on the American people," Republican Rep. Tim Huelskamp of Kansas told National Journal. "Hard-earned taxpayer funds should not be spent for bureaucrats to impose their ideology onto America's plates."

America's dietary guidelines have never before addressed the environmental impact of food cultivation and consumption. But nearly 15 percent of global greenhouse gas emissions come from livestock, according to the United Nations Food and Agriculture Organization.

Environmentalists and their allies want the Agriculture and Health and Human Services departments to make history this year by telling Americans that eating less meat leaves a smaller carbon footprint.

Environmentalists have reason for optimism. In February, the Dietary Guidelines Advisory Committee released a report declaring that "a diet higher in plant-based foods, such as vegetables, fruits, whole grains, legumes, nuts, and seeds, and lower in calories and animal-based foods is more health promoting and is associated with less environmental impact."

But if the spending bills that the House has crafted to set the budgets for the USDA and HHS are signed into law with the provisions calling on the guidelines to stick to diet and nutrition, environmentalists won't get their wish.

On Monday, members of the scientific advisory panel took the unusual step of penning a letter to House Appropriations Committee Chairman Hal Rogers and ranking member Nita Lowey calling for the removal of the riders related to the dietary guidelines.

And Wednesday, Democratic congresswoman Rosa DeLauro tried and failed to strike the provision that would require the guidelines to stick to diet and nutrition from a spending bill intended to set the fiscal year 2016 budget for Health and Human Services.

"These riders are ideologically based. They shouldn't be there," Rep. DeLauro said during an interview in the Capitol on Wednesday. "We're not in the majority so all we can do is make our case, but this needs to be based on science. We've gotta go with science and they keep saying they want to go with science but then when science dictates something they don't agree with they say 'oh well, we don't like that science.'"

Americans have been eating less red meat in recent years. And if the dietary guidelines—a nutritional blueprint that influences that makeup of everything from school lunches to federal meal programs—tell Americans to cut back even further, the industry likely would feel the sting.

Losing market share and under scrutiny for their environmental impacts, the cattle and other livestock industries have rushed to reassure the American public that red meat is a critical ingredient in any balanced diet. They've also argued that dietary guidelines have no business delving into the environmental impact of anyone's eating habits.

A number of industry groups, including the National Cattlemen's Beef Association, the National Pork Producers Council, and the National Chicken Council have registered to lobby on the dietary guidelines.

A coalition of House Republicans, including Mike Pompeo of Kansas, Cynthia Lummis of Wyoming, and Steve King of Iowa signed onto a letter in March suggesting that the government should not take sustainability into account when crafting the 2015 dietary guidelines.

But Democrats and environmentalists have endorsed the idea that America's dietary guidelines should connect the dots between eating habits and the environment.

A coalition of House Democrats, including DeLauro and Bobby Rush of Illinois sent their own letter to Agriculture and Health and Human Services in May, urging the government to stick with the focus on sustainability.

"Sustainability is increasingly important for maintaining a healthy food supply," Democratic congressman Sam Farr told National Journal. "Ignoring that is shortsighted and will make it harder to meet our nutrition requirements in the future."

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