Dr. Marty Makary’s resignation as commissioner of the Food and Drug Administration on Tuesday, May 12, 2026, leaves the agency in the hands of an acting leader who is the first non-scientist to hold the post in more than fifty years, and widens a leadership gap that has defined the Department of Health and Human Services under Secretary Robert F. Kennedy Jr.
Makary’s departure adds the FDA to a growing list of major health agencies operating without Senate-confirmed leadership. The administration has no confirmed surgeon general. NIH Director Jay Bhattacharya has been doubling as acting head of the Centers for Disease Control and Prevention since February. The FDA itself lacked a permanent vaccine chief after that official was ousted for a second time in a year.
“It’s a sign that something is not right in this department,” said Dr. Daniel Jernigan, a former senior employee at the CDC.
The acting FDA commissioner, Kyle Diamantas, is an attorney who previously served as a chief counselor to Kennedy and is a friend of Donald Trump Jr. He now confronts an array of politically sensitive regulatory challenges: developing a first-of-its-kind federal definition of “ultra-processed foods,” which Kennedy blames for elevated rates of diabetes, obesity, and other chronic conditions; ongoing reviews of food dyes, antidepressants, and COVID-19 vaccines; and balancing the anti-regulatory priorities of traditional Republicans with Kennedy’s anti-corporate focus on scrutinizing food and pharmaceutical ingredients. Diamantas himself recently described the ultra-processed foods effort as “really hard” at a health conference.
“Kyle Diamantas now has a nearly impossible charge,” said Dr. Peter Lurie, a former FDA official now at the Center for Science in the Public Interest. “Leading, as a non-scientist, a science-based agency under an unqualified secretary who puts his own medical and nutritional pet peeves over evidence-based public health.”
The CDC has cycled through a succession of short-term directors. The administration’s first pick, former Florida Rep. Dr. David Weldon, saw his March 2025 confirmation hearing canceled an hour before it was scheduled, after Weldon was told not enough senators would support him. His eventual successor, Susan Monarez, was confirmed by the Senate but ousted in less than a month over disagreements on the administration’s agenda. Several senior CDC scientific leaders resigned in protest, saying Monarez’s dismissal ended any hope that a CDC director could insulate the agency’s scientific work from political interference.
Jernigan, who resigned from a senior CDC role last August — a position that has yet to be filled by a permanent replacement — said the leadership shuffle has left no one in place to campaign for critical agency funding or to retain skilled scientists. As the current hantavirus outbreak unfolded, the CDC deployed response teams and Bhattacharya appeared on a Fox News program to urge Americans not to worry, but he got some details wrong and overstated what was known at the time. Jernigan urged the CDC to let more career scientists speak directly to the public.
“That will do more for trust and for calming the nerves of the U.S. right now,” he said.
Kathleen Hall Jamieson, director of the Annenberg Public Policy Center at the University of Pennsylvania, said most Americans do not pay attention to agency leadership until a public health concern arises — such as the hantavirus outbreak. “The key question for me is, when we need these agencies to speak, will they have the capacity to draw the science together and tell us what we need to know?” Jamieson said.
The leadership turmoil coincides with a visible messaging shift at HHS and the White House. After a first year in which Kennedy focused heavily on rolling back vaccine guidelines, the administration has moved in recent months — ahead of the midterm elections — to emphasize diet, lifestyle, and affordability initiatives. The administration’s personnel choices reflect the pivot. Last month, after withdrawing a surgeon general nominee who was embedded in Kennedy’s Make America Healthy Again movement, President Donald Trump nominated Dr. Nicole Saphier, a radiologist and former Fox News personality who has advocated vaccines more forcefully than Kennedy and has at times criticized HHS actions as “embarrassing.” Saphier’s nomination requires Senate confirmation.
Throughout the leadership churn, Kennedy himself has remained the most prominent public voice for the department. That worries Jernigan, who said the secretary does not consistently center the best available science in his decisions.
“The driver for the secretary is the ideology,” Jernigan said. “And that’s not a strategy for really improving the health of Americans.”
HHS did not immediately respond to a request for comment.