Moderate coffee or tea drinking may help protect your brain as you age, lowering dementia risk and slowing cognitive decline. Credit: Shutterstock A large prospective cohort study conducted by researchers from Mass General Brigham, Harvard T.H. Chan School of Public Health, and the Broad Institute of MIT and Harvard examined data from 131,821 participants in the Nurses' Health Study (NHS) and Health Professionals Follow-Up Study (HPFS). The findings showed that moderate intake of caffeinated