“It is an interesting finding on the journey to understanding people’s vulnerability to dementia,” said Dr Mark Fisher, a psychologist who works with dementia suffers on a daily basis through Auckland’s Hinengaro Clinic and wasn’t involved in the study. He cautioned against any bad sleepers rushing out to buy sleeping pills because of the new findings, adding that “people who have short sleep are by no means consigned to getting dementia,” he said. “In fact, most of them won’t.” The study used data from an existing study, which tracked about 8,000 people for 25 years from around age 50. Most of the participants were white, well-educated British males, one of the study’s limitations in comparing its findings to more diverse populations.