You are here

The COSMOS Trial

The COcoa Supplement and Multivitamin Outcomes Study (COSMOS) at Brigham and Women’s Hospital – an affiliate of Harvard Medical School (Boston, MA) and the Fred Hutchinson Cancer Research Center (Seattle, WA) is a clinical trial that will randomize 18,000 men and women across the U.S. The study will investigate whether taking daily supplements of cocoa flavanols (600 mg/day) or a common multivitamin reduces the risk for developing heart disease, stroke, and cancer.

Learn more about COSMOS at

Although results from previous studies have been promising, the health benefits of taking these supplements have not yet been proven. The only way to determine whether or not cocoa flavanol and multivitamin supplements help maintain health is by conducting a large-scale trial, such as COSMOS.

COSMOS launched in May 2015 – announcing the public-private partnership comprised of academia, government, and industry: Brigham and Women’s Hospital, Harvard Medical School, the Seattle-based Fred Hutchinson Cancer Research Center, the National Institutes of Health, Mars, Incorporated and Pfizer Inc.

Currently, COSMOS is recruiting participants. If you are a man aged 60 or older or a woman aged 65 or older, have not previously had a heart attack or stroke, and have not been diagnosed with cancer (other than skin cancer) within the past 2 years, you may be eligible to participate in COSMOS. COSMOS is registered (Study ID: NCT02422745).