That cup of coffee you start your day with may protect your brain — but only if it’s caffeinated, according to a new study.Researchers found people who regularly drank caffeinated coffee or tea had a lower risk of dementia and modestly better cognitive function.The link was strongest at moderate intake levels -- 2 to 3 cups per day of caffeinated coffee or 1 to 2 cups per day of tea.No significant brain benefits were seen among participants who consumed decaf coffee.The results are based on data from nearly 132,000 women and men who filled out dietary questionnaires every 2 to 4 years for up to 4 decades, tracking their intake of caffeinated coffee, decaffeinated coffee, and tea.All of the participants were free of cancer, Parkinson’s disease and dementia at the start. By the end, more than 11,000 had been diagnosed with dementia.The authors note this was an observational study that shows an association but doesn’t prove cause and effect. More research is needed.Source: JAMAAuthor Affiliations: T.H. Chan School of Public Health, Brigham and Women’s Hospital, Harvard University, Broad Institute.Sign up for our weekly HealthDay newsletter