WASHINGTON — A lawsuit filed Wednesday with the U.S. District Court for the District of Columbia alleges federal agencies improperly rewrote the nation’s dietary guidelines.

The suit, brought by the Physicians Committee for Responsible Medicine, a nonprofit that advocates for plant-based diets, claims the Department of Health and Human Services and the U.S. Department of Agriculture used a “secret panel” of scientists backed by the beef and dairy industries to flip the food pyramid. It also alleges the government disregarded federal law that dictates how advisory committees function.

Most of the researchers handpicked by the Trump administration to work on the scientific basis of new guidelines had financial ties to beef, dairy, egg, and other interests. They were chosen behind closed doors and given less than three months to finalize a review of the evidence, which was used to justify new dietary advice, STAT previously reported. That review at times relied on industry-funded science.

“The government allowed the meat and dairy industries to ghostwrite the Dietary Guidelines,” Neal Barnard, a physician and the group’s president, said in a press release. “They put money in industry’s pocket and cholesterol in Americans’ arteries.”

The lawsuit asks the court to order the guidelines be withdrawn and a new guidelines process — one that follows requirements laid out in the Federal Advisory Committee Act — be initiated.

STAT reached out to HHS for comment.

HHS and USDA worked together last year to update the Dietary Guidelines for Americans. The result was an upside-down food pyramid and accompanying guidelines that “embrace saturated fats, halve the recommended fruit and vegetable servings, remove daily alcohol intake limits, and promote fad diets,” the lawsuit says.

Many in the nutrition world were perplexed by the focus on foods like beef, whole milk, cheese and eggs, which contain high amounts of saturated fats, even as dietary guidelines recommended limiting saturated fat consumption.

The new guidance also went against the findings of a 20-person scientific panel that had spent nearly two years reviewing the latest nutrition science, and recommended plant-based diets. Those advisers said eating red meat and saturated fats should be discouraged. (Nine of the 20 had relevant conflicts of interest, according to the watchdog group U.S. Right to Know.)

The lawsuit alleges the government broke the law when it disregarded the findings of that earlier dietary guidelines committee, which was assembled under President Biden, and followed FACA rules.

The public was not aware of the secondary science group formed under Trump, or how it conducted its work, until a “scientific foundation” document appeared on a government website on Jan. 7 — the day the new guidelines were released.