The Checkup Creators & Guests

Mikhail Varshavski, commonly known as Doctor Mike, is a Russian–American internet celebrity doctor.

Anjelah Johnson Reyes is an actress, comedian, and former NFL cheerleader.

Steve-O is a television personality, stunt performer, actor, writer, stand-up comedian, and musician, best known for as part of the Jackass television and movie series. His entertainment career is mostly centered on his performance stunts on the American television series Jackass (2000–2002) and its related movies including Jackass: The Movie (2002), Jackass Number Two (2006) and Jackass 3D (2010), as well as its spin-off series Wildboyz (2003–2006).Steve-O also has a successful YouTube channel and hot sauce.

Dane Cook is an American stand-up comedian and film actor. He has released five comedy albums: Harmful If Swallowed; Retaliation; Vicious Circle; Rough Around The Edges: Live From Madison Square Garden; and Isolated Incident.

Marion Nestle is an academic, Paulette Goddard professor of nutrition, food studies, and public health at New York University, professor of Sociology at NYU, and a visiting professor of nutritional sciences at Cornell University.

Marques Brownlee is a YouTuber.

Kamala Harris is the 49th Vice President of the United States, serving since January 2021. She is the first woman, the first Black woman, and the first South Asian American to hold the office. Prior to her vice presidency, Harris built a prominent career in law and politics. She served as the Attorney General of California from 2011 to 2017, where she was noted for her work on criminal justice reform, consumer protection, and civil rights. In 2017, Harris became the U.S. Senator from California, gaining recognition for her role in Senate committees and her sharp questioning during key hearings. Throughout her career, Harris has been a trailblazer for women and people of color in American politics. Harris is the Democratic nominee for president in the 2024 U.S. presidential election.

Tony Hale is a talented actor and comedian known for his distinctive characters and comedic timing. Born in West Point, New York, Hale gained widespread recognition for his role as Buster Bluth on the cult-favorite series "Arrested Development" (2003-2019). He won two Primetime Emmy Awards for his portrayal of Gary Walsh on the HBO series "Veep" (2012-2019). Hale's voice acting work includes roles in animated films like "Toy Story 4" (2019) and series such as "Archibald's Next Big Thing" (2019- 2020). He continues to captivate audiences with his unique blend of humor and heartfelt performances in both television and film.

Dr. Paul Offit is a pediatrician specializing in infectious diseases, vaccines, immunology, and virology.

Dr. David Spiegel is Willson Professor and Associate Chair of Psychiatry & Behavioral Sciences, Director of the Center on Stress and Health, and Medical Director of the Center for Integrative Medicine at Stanford University School of Medicine, where he has been a member of the academic faculty since 1975, and was Chair of the Stanford University Faculty Senate from 2010-2011.

Hannah Fry is a British mathematician, lecturer on the Mathematics of Cities, television presenter and public speaker. Her work includes studying the patterns of human behavior, such as relationships and dating and how mathematics can apply to them.

Dr. Matthew Walker is a scientist and Professor of Neuroscience & Psychology. at the University of California, Berkeley.

Dr. Rena Malik is a urologist and pelvic surgeon.

Sebastian Maniscalco is a popular American stand-up comedian and actor known for his energetic stage presence and observational humor. He has released several successful comedy specials, including "Stay Hungry" and "Aren't You Embarrassed?" Maniscalco has also made a mark in film with roles in "Green Book" and "The Irishman." His unique comedic style, characterized by animated storytelling and physical comedy, has earned him a dedicated fan base and critical acclaim, establishing him as one of the leading comedians of his generation.

Dr. Mike Israetel is a well-known figure in the fitness and bodybuilding community, recognised for his expertise in sports science, particularly in the areas of hypertrophy (muscle growth), strength training, and nutrition.

Kal Penn is an actor, comedian, producer, and former civil servant. He is known for his role portraying Lawrence Kutner on the television program House as well as the character Kumar Patel in the Harold & Kumar film series.

Barbara Corcoran is a businesswoman, investor, speaker, consultant, syndicated columnist, author, and television personality.

Dr. Jason Fung is a medical director, kidney specialist, and author.