People who sleep less than six hours a night are four times more likely to catch a cold.
Cold faster
For the study, the sleeping behavior of a group of volunteers was monitored for a week. They then went into quarantine, where they were given nasal drops containing a cold virus. Those who slept briefly were found to catch a cold four times as often.
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The study doesn't prove that too little sleep makes you catch a cold, but it does indicate that there is indeed a link between sleep deprivation and a weakened immune system.
