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Lack of Sleep Increases the Risk of Catching a Cold
As cold season approaches, many Americans stock up on their vitamin C and Echinacea(紫锥 花精油). But following the age -old advice about catching up on sleep might be more important.
Studies have demonstrated that poor sleep and susceptibility (易受影响) to colds go hand in hand, and scientists think it could be a reflection of the role sleep plays in maintaining the body’s defenses.
In a recent study for the Archives of Internal Medicine, scientists followed 153 men and women for two weeks, keeping track of their quality and duration of sleep. Then, during a five - day period, they quarantined(进行检疫隔离) the subjects and exposed them to cold viruses. Those who slept an average of fewer than seven hours a night, it turned out, were three times as likely to get sick as those who averaged at least eight hours.
Sleep and immunity, it seems, are tightly linked. Studies have found that
A. They checked the subjects’health problems and gave advice.
B. They made record of the subjects’quality and length of sleep.
C. They exposed the subjects to different kinds of viruses.
D. They gave medicine to the subjects who had caught col