The study has its origin, strangely enough, in tea. Back in 2006, researchers thought tea drinkers might have fewer heart attacks. So Kenneth Mukamal, an epidemiologist at the Harvard-affiliated Beth Israel Deaconess Medical Center in Boston, recruited at-risk adults and told them to drink either three cups of black tea a day or three cups of water. Getting participants to stick to the program is notoriously difficult, so to make sure they were drinking their tea, Mukumal tested urine samples from a subgroup of participants for gallic acid, a tea breakdown product. After six months, they ran the numbers: Tea had virtually no effect on a person’s cardiovascular risk.