Marc Siegel

Marc Siegel is married to Ludmilla Luda Siegel, a physician and neurologist, and they have three children. Their son Samuel experienced hearing problems after birth that were resolved after his ear canals were cleared, although he later had repeated ear infections.

Siegel is Jewish and has cited the Oath of Maimonides as an influence on his approach to medical ethics.

Siegel attended Brown University from 1974 to 1978 and received his Doctor of Medicine degree from the State University of New York at Buffalo in 1985. He completed his internal-medicine residency at New York University Medical Center in 1988 and received American Board of Internal Medicine certification in 1991.

He practices adult internal medicine as a primary-care physician in New York. His clinical work includes managing chronic conditions such as diabetes, high blood pressure, and cardiovascular disease, along with preventive care, immunizations, and annual physicals. He is affiliated with NYU Langone Hospitals and holds the position of clinical professor in the Department of Medicine at NYU Grossman School of Medicine.

Siegel's books on infectious disease include False Alarm: The Truth About the Epidemic of Fear (2005), Bird Flu: Everything You Need to Know About the Next Pandemic (2006), and Swine Flu: The New Pandemic (2009). These works argue for distinguishing between genuine public-health threats and diseases that receive disproportionate media attention. He promoted False Alarm during a 2005 appearance on The Daily Show with Jon Stewart.

His 2011 book The Inner Pulse: Unlocking the Secret Code of Sickness and Health examines the relationship between the physical and spiritual aspects of healing. He later wrote COVID: The Politics of Fear and the Power of Science (2020), a book about medical advances, pandemic decision-making, and the role of media and politics in shaping public fear.

His book The Miracles Among Us: How God's Grace Plays a Role in Healing was announced for publication in 2025. The book connects faith, spirituality, medicine, and personal stories of recovery.

Siegel is the medical director of Doctor Radio on SiriusXM and has hosted Doctor Radio Reports, a program focused on the COVID-19 pandemic and public-health measures. He also serves as a senior medical correspondent or contributor for Fox News, where he comments on infectious disease, vaccination, health policy, and the medical condition of public figures.

During the COVID-19 pandemic, Siegel discussed changing public-health guidance, vaccination, masking, and booster shots. He interviewed Dr. Anthony Fauci on Doctor Radio in 2021 and again in 2022. His media work and writing have also appeared in USA Today, The Wall Street Journal, The Hill, and The New York Post.

Siegel has commented on the health records of presidential candidates and reviewed Senator John McCain's medical records during McCain's 2000 presidential campaign. He also interviewed President Donald Trump about his health, including a cognitive evaluation in which Trump recited the words "person, woman, man, camera, TV."

Siegel has written and spoken about swine flu, SARS, avian influenza, COVID-19, and mpox. During the 2009 swine-flu outbreak, he supported using Tamiflu for children at summer camps with confirmed outbreaks, a position that differed from guidance urging more limited use. During the 2022 to 2023 mpox outbreak, he advocated faster distribution of vaccines and treatments to areas most affected.

His health-policy commentary has included criticism of parts of the Affordable Care Act, especially its insurance networks, deductibles, and essential-benefits requirements. He also supported calorie labeling in restaurants, citing research that linked menu labeling with lower daily calorie intake.

Siegel has argued that the public should focus on common and consequential health threats rather than illnesses that receive the most media attention. His writing also emphasizes communication between doctors and patients, preventive care, and making complex medical information accessible to the general public.