There's a love mattress that is specifically designed for couples who sleep on each other's arms.
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Dieters who sleep more take off more fat that those who sleep less.
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Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
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Honeybees never sleep.
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In China, teachers allow children to sleep in class for around 20 minutes to help improve their learning.
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Some people have a "natural alarm clock" allowing them to wake up when they want. This is actually caused by a burst of the stress hormone adrenocorticotropin.
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A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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Cows can sleep standing up, but they can only dream lying down.
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