Signs of sleep debt found in the blood
Going without slumber makes metabolic molecules dwindle
![Person napping](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2015/02/kb_shutterstock_178353305.jpg?fit=860%2C460&ssl=1)
DON’T SNOOZE, YOU LOSE Scientists can identify when people are sleep deprived by noting declines in certain molecules in their blood.
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