Previous research has found that people who generally have more positive emotions tend to experience a broad range of benefits—more stable marriages, better social skills and just greater happiness overall—compared with those who are more dominated by negative emotions. One measurement that researchers use when assessing emotions is smile intensity, based on the premise that the authenticity of your grin conveys the depth of your positive emotions. In a study recently published in the journal Psychological Science researchers from Wayne State University analyzed the smiles of 230 Major League Baseball players from the 1952 player register to determine how positive emotions influence longevity. By blowing up images from player cards, researchers assessed player smiles—categorizing them as “no smile,” “partial smile” and what is known as a “Duchenne smile,” or the authentic, spontaneous expression of happiness named for a 19th century French neurologist. They found that, players who had more authentic smiles—conveying a deeper level of contentment—were more likely to live longer than those who were only partially smiling, or not grinning at all.
