Millons of people today are in serious ‘debt’. This can be a major factor in wrecking their cars, damaging their careers and even ruining their marriages. It can adversely affect their health and lifespan. It is a deficit that contributes to immune suppression, creating susceptibility to various infections. Conditions as different as diabetes, heart diseases, and extreme obesity, as well as other health problems have been linked to it. Yet, most victims are oblivious of this debt. The debtor is the one who does not have enough sleep needed for well-being. This can be caused by voluntary sleep deprivation resulting from a person’s life-style or by involuntary sleep deprivation because of illness and other causes. Medical researchers estimate that the earth’s population is now getting on the average an hour less sleep per into both the variety of sleep-related illnesses and their impact on the quality of life.  The medical world once viewed the chronic inability to sleep as just one disorder, commonly called insomnia. However, a commission created by the U.S. Congress recognized 17 distinct sleep disorders. At any rate, insomnia has so many causes that it is often considered to be a sympt5om of other problems, much as fever suggests some sort of infection. Even occasional deprivation of sleep can be disastrous. Consider the case of Tom, although an experienced truck driver, he plunged his 18-wheel vehicle over an embankment, spilling 400 litres of sulphuric acid onto a major highway. Tom admits: ‘I fell asleep.’ Students of two U.S. highways estimated that drowsy drivers caused some 50 per cent of the fatal crashes.   With hundreds of thousands of sleep-related auto and other accidents happening annually, the worldwide coast to productivity and family is enormous. What factors may contribute to lack of sleep? ‘One is the social phenomenon often called 24/7- operating 24 hours a day, seven days a week. The newspaper, USA Today, described this as a cultural earthquake that is changing the way we live, noting that a new wave of round-the-clock retailers and services is profiting by mocking the clock. In many lands, people watch all-night television programmes and access the internet when they should be sleeping. Then there is the toll taken by emotional disorders, often involving anxieties heightened by stress occasioned by the pace of life. Also, there are a variety of physical diseases that can contribute to lack of sleep.   Many doctors note how difficult it is to get their patients to take sleep seriously. One doctor complained that chronic fatigue is even considered ‘a status symbol’ by some. And because their condition often worsens very gradually, victims of sleep deprivation may not recognize that they suffer from a serious sleep disorder. Many of them reason, ‘I’m just getting old’ or I’ can’t cope with life, so I tend to shut down’ or ‘I’m tired all the time because I can never get the long rest I need.’ Reversing this sleep debt is a complex challenge. But understanding how a healthful sleep cycle works and learning to identify the signs of sleep debt can provide the motivation to change. Recognizing the symptoms of a serious sleep disorder can save lives and this should be a warning to many Nigerians, particularly those who engage in long night journeys.
Which of the following is true according to the passage?
A. lack of sleep is caused by either a person's lifestyle or involuntary sleep and not by both B. voluntary sleeep deprived can be attributed to the way in which an individual lives C. some illnesss causes sleep disorder which can be both voluntary and in voluntary D. healthful sleep is needed only for one's well-being