This article by Darius Tahir first appeared in KFF Health News, republished with permission.

President-elect Donald Trump’s choice to run the sprawling government agency that administers Medicare, Medicaid, and the Affordable Care Act marketplace — celebrity doctor Mehmet Oz — recently held broad investments in health care, tech, and food companies that would pose significant conflicts of interest.

Oz’s holdings, some shared with family, included a stake in UnitedHealth Group worth as much as $600,000, as well as shares of pharmaceutical firms and tech companies with business in the health care sector, such as Amazon. Collectively, Oz’s investments total tens of millions of dollars, according to financial disclosures he filed during his failed 2022 run for a Pennsylvania U.S. Senate seat.

Trump said Tuesday he would nominate Oz as administrator of the Centers for Medicare & Medicaid Services. The agency’s scope is huge: CMS oversees coverage for more than 160 million Americans, nearly half the population. Medicare alone accounts for approximately $1 trillion in annual spending, with over 67 million enrollees.

UnitedHealth Group is one of the largest health care companies in the nation and arguably the most important business partner of CMS, through which it is the leading provider of commercial health plans available to Medicare beneficiaries.

UnitedHealth also offers managed-care plans under Medicaid, the joint state-federal program for low-income people, and sells plans on government-run marketplaces set up via the Affordable Care Act. Oz also had smaller stakes in CVS Health, which now includes the insurer Aetna, and in the insurer Cigna.

It’s not clear if Oz, a heart surgeon by training, still holds investments in health care companies, or if he would divest his shares or otherwise seek to mitigate conflicts of interest should he be confirmed by the Senate. Reached by phone on Wednesday, he said he was in a Zoom meeting and declined to comment. An assistant did not reply to an email message with detailed questions.

“It’s obvious that over the years he’s cultivated an interest in the pharmaceutical industry and the insurance industry,” said Peter Lurie, president of the Center for Science in the Public Interest, a watchdog group. “That raises a question of whether he can be trusted to act on behalf of the American people.” (The publisher of KFF Health News, David Rousseau, is on the CSPI board.)

Oz used his TikTok page on multiple occasions in November to praise Trump and Robert F. Kennedy Jr., including their efforts to take on the “illness-industrial complex,” and he slammed “so-called experts like the big medical societies” for dishing out what he called bad nutritional advice. Oz’s positions on health policy have been chameleonic; in 2010, he cut an ad urging Californians to sign up for insurance under President Barack Obama’s Affordable Care Act, telling viewers they had a “historic opportunity.”

Oz’s 2022 financial disclosures show that the television star invested a substantial part of his wealth in health care and food firms. Were he confirmed to run CMS, his job would involve interacting with giants of the industry that have contributed to his wealth.

Given the breadth of his investments, it would be difficult for Oz to recuse himself from matters affecting his assets, if he still holds them. “He could spend his time in a rocking chair” if that happened, Lurie said.

In the past, nominees for government positions with similar potential conflicts of interest have chosen to sell the assets or otherwise divest themselves. For instance, Treasury Secretary Janet Yellen and Attorney General Merrick Garland agreed to divest their holdings in relevant, publicly traded companies when they joined the Biden administration.

Trump, however, declined in his first term to relinquish control of his own companies and other assets while in office, and he isn’t expected to do so in his second term. He has not publicly indicated concern about his subordinates’ financial holdings.

CMS’ main job is to administer Medicare. About half of new enrollees now choose Medicare Advantage, in which commercial insurers provide their health coverage, instead of the traditional, government-run program, according to an analysis from KFF, a health information nonprofit that includes KFF Health News.

Proponents of Medicare Advantage say the private plans offer more compelling services than the government and better manage the costs of care. Critics note that Medicare Advantage plans have a long history of costing taxpayers more than the traditional program.

UnitedHealth, CVS, and Cigna are all substantial players in the Medicare Advantage market. It’s not always a good relationship with the government. The Department of Justice filed a 2017 complaint against UnitedHealth alleging the company used false information to inflate charges to the government. The case is ongoing.

Oz is an enthusiastic proponent of Medicare Advantage. In 2020, he proposed offering Medicare Advantage to all; during his Senate run, he offered a more general pledge to expand those plans. After Trump announced Oz’s nomination for CMS, Jeffrey Singer, a senior fellow at the libertarian-leaning Cato Institute, said he was “uncertain about Dr. Oz’s familiarity with health care financing and economics.”

Singer said Oz’s Medicare Advantage proposal could require large new taxes — perhaps a 20% payroll tax — to implement.

Oz has gotten a mixed reception from elsewhere in Washington. Pennsylvania Sen. John Fetterman, the Democrat who defeated Oz in 2022, signaled he’d potentially support his appointment to CMS. “If Dr. Oz is about protecting and preserving Medicare and Medicaid, I’m voting for the dude,” he said on the social platform X.

Oz’s investments in companies doing business with the federal government don’t end with big insurers. He and his family also hold hospital stocks, according to his 2022 disclosure, as well as a stake in Amazon worth as much as nearly $2.4 million. (Candidates for federal office are required to disclose a broad range of values for their holdings, not a specific figure.)

Amazon operates an internet pharmacy, and the company announced in June that its subscription service is available to Medicare enrollees. It also owns a primary care service, One Medical, that accepts Medicare and “select” Medicare Advantage plans.

Oz was also directly invested in several large pharmaceutical companies and, through investments in venture capital funds, indirectly invested in other biotech and vaccine firms. Big Pharma has been a frequent target of criticism and sometimes conspiracy theories from Trump and his allies. Kennedy, whom Trump has said he’ll nominate to be Health and Human Services secretary, is a longtime anti-vaccine activist.

During the Biden administration, Congress gave Medicare authority to negotiate with drug companies over their prices. CMS initially selected 10 drugs. Those drugs collectively accounted for $50.5 billion in spending between June 1, 2022, and May 31, 2023, under Medicare’s Part D prescription drug benefit.

At least four of those 10 medications are manufactured by companies in which Oz held stock, worth as much as about $50,000.

Oz may gain or lose financially from other Trump administration proposals.

For example, as of 2022, Oz held investments worth as much as $6 million in fertility treatment providers. To counter fears that politicians who oppose abortion would ban in vitro fertilization, Trump floated during his campaign making in vitro fertilization treatment free. It’s unclear whether the government would pay for the services.

In his TikTok videos from earlier in November, Oz echoed attacks on the food industry by Kennedy and other figures in his “Make America Healthy Again” movement. They blame processed foods and underregulation of the industry for the poor health of many Americans, concerns shared by many Democrats and more mainstream experts.

But in 2022, Oz owned stakes worth as much as $80,000 in Domino’s Pizza, Pepsi, and US Foods, as well as more substantial investments in other parts of the food chain, including cattle; Oz reported investments worth as much as $5.5 million in a farm and livestock, as well as a stake in a dairy-free milk startup. He was also indirectly invested in the restaurant chain Epic Burger.

One of his largest investments was in the Pennsylvania-based convenience store chain Wawa, which sells fast food and all manner of ultra-processed snacks. Oz and his wife reported a stake in the company, beloved by many Pennsylvanians, worth as much as $30 million.KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.

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This article first appeared on KFF Health News and is republished here under a Creative Commons license.