Calley Means—a top ally to anti-vaccine Health Secretary Robert F. Kennedy Jr. and a co-author of the so-called “MAHA bible”—resigned from his role in the Trump administration Thursday, reportedly in frustration over delays to food policy changes sought by the Make America Healthy Again movement.

“I am resigning from the White House with tremendous respect for President Trump and Bobby Kennedy,” Means wrote in a social media post this afternoon. “It was an honor to advocate for MAHA moms in the administration and steer policies like Dietary Guidelines reform, psychedelic reform, removing soda from SNAP, removing food dyes, GRAS reform, and overhauling government food procurement.”

His post did not provide a reason for his departure. Means served as a senior advisor to Kennedy.

Sources close to Means told The Wall Street Journal that he had grown frustrated in the position. Means reportedly blamed other members of the administration for allowing the food industry and special interests to have too much sway in policy decisions. One source described Means as “disillusioned.”

The Journal recently reported that the White House had punted on two of Kennedy’s food priorities: defining and regulating ultraprocessed foods, and regulations that would require school meals to have more protein and less sugar. In recent meetings, Means reportedly raised his voice and grew visibly frustrated over the lack of progress on such issues. Others in the administration complained he was unwilling to make political concessions.

Means’ resignation comes as members of the MAHA movement have grown increasingly critical of Kennedy’s inability to follow through with key policy priorities. There is also growing backlash to Kennedy’s seeming embrace of corporate interests. A MAHA summit last month drew scorn for having numerous corporate sponsors, including Walmart, UnitedHealth, Anthropic, OpenAI, and Grail. Sponsorship packages were reportedly sold for up to $300,000. At the summit, Kennedy sat down for a “fireside chat” with Vice President JD Vance and extolled the potential of artificial intelligence. Many MAHA members and leaders felt betrayed by the corporate involvement, saying it was antithetical to the grassroots nature of the MAHA movement.

Means is among the early leaders of the grassroots effort. Along with his sister, Casey Means, he co-authored a book considered the “MAHA bible,” titled Good Energy: The Surprising Connection Between Metabolism and Limitless Health. The book provides a potpourri of dietary and lifestyle advice, including recommendations to avoid processed foods, seed oils, fragrances, various home care products, fluoride, unfiltered water, bananas (when eaten alone), receipt paper, and birth control pills. One of its chapters is titled “Trust Yourself, Not Your Doctor.”

Trump nominated Casey Means to be surgeon general, but her nomination was abandoned amid misgivings over her medical qualifications, positions on vaccines, and promotion of unproven wellness claims.