Though coffee didn’t have the same associations as smoking or drinking, Kamangar says, “the connotation was that this is not a good thing.” People have been drinking coffee for centuries, and scientists have been studying its health effects for nearly as long. According to geneticist Marilyn Cornelis, scientists are simply conducting research better. In the 1970s and 1980s, several studies found negative relationships between coffee and health, including a popular 1981 paper that found an association between coffee drinking and pancreatic cancer. People who smoke or have higher stress levels, for example, tend to both drink more coffee and have worse health outcomes.