A if the term vegetarian cannot be misleading

 
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Many modern investigators have done research in the field of sleep and their conclusions have often 
differed extensively. Yet they all have agreed on one point: sleep is nature's great restorer. Sleep induces 
such aspects as absence of voluntary motion, loss of awareness and the harsh sounds that we call snoring. 
There are also changes in metabolism, in the pulse rate, in blood pressure, in bodily temperature, in nerve 
functions and in the nature of bodily reflexes. Sleep is characteristic of both plant and animal life. There 
were several theories at the start of the present century to answer the question "Why do we sleep?". 
According to one of them, nerve cells shrank throughout waking hours so we couldn't make contact with 
other people any more and became sleepy. Another theory was that some sort of toxin accumulated during 
waking hours. In time, this toxin would affect the nervous system so that it would slow down. According to 
the most widely accepted explanation-the so called "cerebral-anaemia" theory-sleep was brought about 
because the blood supply to the brain diminished. However, today we know that none of these theories 
were valid. For instance, it has been proven that the blood supply to the brain increases during sleep. This 
is accurately the opposite of "cerebral-anaemia" theory. In fact, this increased circulation has a restorative 
value. What are some disorders of sleep? Somnambulism is very common. About 40% of university 
students talk in their sleep. When they wake up, they don't remember anything. Another disorder, 
somnambulism, is not so common. You may have seen people walking while they are sleeping. This may 
result from an emotional disturbance and the person again doesn't remember anything when he wakes up. 
Muscle cramps sometimes disturb sleep as well. (Of course they may also occur when one is awake.) 
Insomnia, or inability to go to sleep is one of the most common conditions about which adults should consult 

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