According to a research review, adults require an average of 8.5 hours of sleep each night to report improvements in performance, alertness and mood. This did not seem to differ between genders. Obtaining less than six hours of sleep a night can lead to severe sleep deprivation. Chronic sleep deprivation has many negative impacts on our health including reduced motor & cognitive performance, lower mood, and an imbalance in metabolism and hormones. Fatigue is responsible for 10% of all fatal car accidents behind alcohol (18%) and poor attention (15%).

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