How long wilt thou asleep, O sluggard? when wilt thou arise out of thy sleep?
– Proverbs 6:9
[C]ease to sleep longer than is needful; retire to thy bed early, that ye may not be weary; arise early, that your bodies and your minds may be invigorated.
– D&C 88:124
According to a study done by the University of Heidelberg in Germany, people who sleep longer than nine hours a day demonstrated higher mortality rates over a ten-year time period. Professor Dieter Riemann recently presented the results of this study to a meeting of the World Association of Sleep Medicine (WASM) in Berlin.
The study showed that the mortality rate of those who slept on average between seven and eight hours per night was 5% over the duration of the ten-year study. The mortality rate for those sleeping nine hours or more was 11-12%, or roughly twice as high. Riemann noted that this data agrees with data from the USA and Japan. Even though Riemann admitted that any link remains unclear, he explained that all participants in the study had been healthy when the study began.
These findings also corroborate a much earlier study done sometime before approx. 64 A.D. and recorded probably after the end of the Jewish Revolt in 74 A.D.:
And there sat in a window a certain young man named Eutychus, being fallen into a deep sleep: and as Paul was long preaching, he sunk down with sleep, and fell down from the third loft, and was taken up dead. (Acts 20:9)
This very early study into the dangers of too much sleep was very conclusive but is now more so as a result of the Heidelberg study.
Ben Franklin must feel vindicated after the bad rap that Mark Twain gave him. (See Letter from Mark Twain, San Francisco Alta California, July 25, 1869 (“If it had not been for [Benjamin Franklin], with his incendiary “Early to bed and early to rise,” and all that sort of foolishness, I wouldn’t have been so harried and worried and raked out of bed at such unseemly hours when I was young. The late Franklin was well enough in his way; but it would have looked more dignified in him to have gone on making candles and letting other people get up when they wanted to.”))