Dr. Ethan Weiss, MD
Not yet claimedPreventive cardiologist, Cardiologist · Physician (MD)
San Francisco, CA · Telehealth in 0 states
UCSF cardiologist and Associate Professor of Medicine specializing in preventive cardiology, with research interests in coronary disease genetics, cardiovascular risk assessment and metabolic disorders such as obesity and fatty liver disease.
About Dr. Ethan Weiss, MD
Updated Sep 20, 2026 · next review Dec 19, 2026Dr. Ethan J. Weiss is a cardiologist based in the San Francisco area. He earned his medical degree at Johns Hopkins University School of Medicine in 1996, did his internship and residency at Johns Hopkins, and completed a cardiology fellowship at UCSF that included three years of thrombosis research at the Cardiovascular Research Institute.
His listed clinical focus is preventive cardiology, including cardiovascular risk assessment, the genetics of coronary disease, and heart disease in younger people. His research has covered metabolic conditions such as obesity, fatty liver, and diabetes, as well as blood clotting. He was an Associate Professor of Medicine at UCSF and an investigator at the UCSF Cardiovascular Research Institute, and a listed hospital affiliation is UCSF Helen Diller Medical Center at Parnassus Heights.
He was senior author of the TREAT randomized trial published in JAMA Internal Medicine in 2020, which found no significant difference in weight loss between time-restricted eating and consistent meal timing. He has also co-authored work in Science on metabolism and fatty liver in mice.
In 2024 he co-founded Marea Therapeutics, a cardiometabolic biotech company in South San Francisco, where he is Chief Scientific Officer. Trade press reported that he left his UCSF faculty position to work at the company full time. In CMS Open Payments data for 2021 through 2025, he has no reported industry payments ($0 across 0 records).
- Medical school and training
- Medical degree from Johns Hopkins University School of Medicine in 1996, with internship and residency at Johns Hopkins and a cardiology fellowship at UCSF. healthgrades.com
- Preventive cardiology focus
- His UCSF profile lists preventive cardiology, cardiovascular risk assessment, genetics of coronary disease, and heart disease in the young. profiles.ucsf.edu
- UCSF faculty and researcher
- Served as Associate Professor of Medicine at UCSF and an investigator at the UCSF Cardiovascular Research Institute. ucsfhealthcardiology.ucsf.edu
- Led fasting clinical trial
- Senior author of the TREAT randomized trial in JAMA Internal Medicine (2020), which found time-restricted eating did not produce more weight loss than consistent meal timing. ucsf.edu
- Biotech co-founder
- Co-founder and Chief Scientific Officer of Marea Therapeutics, a cardiometabolic biotech that launched in 2024 with $190 million. businesswire.com
- Published research record
- Co-author of a 2022 Science paper on an immunity–metabolism trade-off linked to fatty liver in mice; a full publication list is on his UCSF Department of Medicine page. medicine.ucsf.edu
- Hospital affiliation listed
- Directory listings name UCSF Helen Diller Medical Center at Parnassus Heights as a hospital affiliation. healthgrades.com
- No industry payments reported
- CMS Open Payments shows $0 in reported industry payments across 0 records for 2021 through 2025. Industry payments are common and legal, and none were reported here. openpaymentsdata.cms.gov
Worth knowing
- Trade press reported that he resigned his UCSF faculty position to work full time at Marea Therapeutics, and he has been described as a volunteer associate professor at UCSF. Patients should confirm whether he is currently seeing patients. cen.acs.org
- He co-founded Keyto, Inc., a consumer ketogenic-diet breath sensor and app company, and co-authored a 2020 trial protocol comparing the Keyto product with another weight-loss app. This is a commercial interest connected to his diet-related research. prnewswire.com
- Board certification in cardiovascular disease was not independently confirmed in this research; no board or state record was retrieved, though directory pages list him under cardiovascular disease. doctor.webmd.com
Industry payments (CMS Open Payments)
Open the CMS recordFederal law requires drug and device companies to report what they pay clinicians: meals, travel, speaking, consulting, and research. Payments are common and legal; the point is that you can see them.
No general payments reported for this NPI from 2021 through 2025.
Sources: ucsfhealth.org · ucsfhealthcardiology.ucsf.edu · medicine.ucsf.edu · profiles.ucsf.edu · healthyheart.ucsf.edu · businesswire.com · twitter.com · healthgrades.com. Something wrong or out of date? Tell us and we will correct it.
Summary prepared with AI assistance from the public sources linked above, reviewed every three months. It is not a review, a rating, or an endorsement.
Practice location
UCSF Center for Prevention of Heart and Vascular Disease
535 Mission Bay Blvd. South
San Francisco, CA 94158
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