World’s largest sleep study shows too much sleep can be bad for your brain - Preliminary results have shown that people who sleep on average between 7 to 8 hours per night performed better cognitively than those who slept less, or more, than this amount (n>10,000).

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World’s largest sleep study shows too much sleep can be bad for your brain - Preliminary results have shown that people who sleep on average between 7 to 8 hours per night performed better cognitively than those who slept less, or more, than this amount (n>10,000).