美国睡眠基金会建议成年人每天的睡眠时间为7-9个小时。不过根据该基金会的数据,20%的美国人每晚睡眠时间不足6小时,近三分之一的人因担心财务状况失眠。因而,睡眠不足正在严重损害着人类的健康。长期的睡眠不足会加大患心血管病、抑郁症、糖尿病和肥胖的风险,损害认知功能、记忆力和免疫系统,每年还会引发超过10万起机动车事故。睡眠不足还会改变身体的新陈代谢 The American Sleep Foundation recommends that adults sleep for 7-9 hours a day. However, according to the foundation, 20% of Americans sleep less than 6 hours per night, with nearly a third of people worried about financial distress. Thus, lack of sleep is seriously detrimental to human health. Long-term lack of sleep can increase the risk of cardiovascular disease, depression, diabetes and obesity, impair cognitive function, memory, and immune system, triggering more than 100,000 motor vehicle accidents each year. Insufficient sleep can also change the body’s metabolism