Eight hours of nightly sleep is not the health panacea you were brought up to believe, according to a study released suggesting a link between too much slumber and a shorter life span.
Sleep experts immediately sought to discredit the conclusions and said they will only cause confusion.
The study, published in the Archives of General Psychiatry, included 1.1 million men and women and found a longer life span among those who sleep six to seven hours a night. The lifespan declines progressively among those who sleep eight hours or longer.
"Our study shows the average sleep for Americans of seven hours per night is safest," said Dr. Daniel Kripke, who led the study. Kripke is a professor of psychiatry who specializes in sleep research at the Univ. of California, San Diego. "You don't have to sleep eight hours per night; it's safe to sleep five, six or seven hours."
The study showed people who slept 9 or 10 hours per night had a similar risk of dying to people with moderate obesity. Risk of death increased by 15 percent for those who slept 8 hours a night, 20 percent for those who get 9 hours of sleep and 35 to 40 percent for those who sleep 10 hours a night.
"This is a happy message for five, six, seven hour sleepers and insomniacs that there's nothing to worry about. This is reassuring," said Kripke.
The National Sleep Foundation, which recommends eight hours of sleep per night for optimal health, immediately attacked the study's findings and said they can do nothing but cause the public unnecessary confusion and concern.
In your main post, use what you have learned in this course so far (observation/experiment, sampling, bias, descriptive statistics, etc.) to critique this study.
- Do you agree or disagree with the study? Support your case using statistics. Present a summary of at least 4 sentences defending your position.