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Morning people may live longer than night owls, a new study suggests. Researchers studied 433,268 people, aged 38 to 73, who defined themselves as either “definite morning” types, “moderate morning” types, “moderate evening” types or “definite evening” types. They followed their health for an average of six-and-a-half years, tracking cause of death with death certificates. The study is in Chronobiology International. (Bakalar, 4/12)

Scientists have long studied whether night owls are saddled with health impacts — some research has linked a preference for sleeping late to higher rates of diabetes, heart disease and obesity, among others. But little was known on whether there was a link between sleeping late and the ultimate outcome: an earlier death. "We wanted to see whether this translated also into an increased risk of mortality and no one had done that before," said lead author Kristen Knutson, an anthropologist at Northwestern University. (Khan, 4/11)