You’ve counted sheep, drunk warm milk. Yet, the night just seems to stretch on. What could you possibly do in such a situation?
Sleep and the cellphone
If new research is to be believed, staying away from chatting on your cellphone in the evening might just help. As insomnia appears to be on the rise—one US study says it has increased 60% in the past five years—the cellphone appears to be just one in a list of seemingly innocuous everyday items and lifestyle patterns that interfere with our ability to get a good night’s sleep.
Researchers from Sweden’s Karolinska Institute and Wayne State University in the US studied 35 men and 36 women between the ages of 18 and 45. Half of them were exposed to radiation that would normally be emitted by a cellphone in use. The other half were told they were receiving that radiation, but were not.
The group exposed to radiation before going to sleep took longer to go into the stage of deep sleep, and also spent less time in deep sleep, compared with the other group. Of the five stages of sleep delineated by scientists, deep sleep is the time when the brain repairs damage done during the day and rejuvenates itself, so that one feels refreshed in the morning.
No one is sure how cellphone radiation affects sleep. One of the study researchers was quoted as saying that it could be associated with specific areas of the brain responsible for activating and coordinating stress. Another theory is that it might affect the production of a hormone called melatonin, which modulates the body’s biological clock and therefore our sleep-wake patterns.
In a country where cellphones are now ubiquitous, this study could have wide implications. R.L. Mani, a sleep medicine pioneer in India and consultant at New Delhi’s Fortis Hospital, says: “Insomnia is a problem and appears to be on the increase.” But cellphones are far from being the only culprit. “Stress is a major factor” says Dr Mani, “So are habits such as working late and getting up early inthe morning, Internet chats, stimulants and drugs.”
Insomnia and low immunity
Yet sleep, as numerous studies have shown, is essential not only for our well-being but also for our survival. Rats, for example, usually live for two or three years. But rats who were deprived of sleep in the laboratory survived only three weeks. They also had low body temperatures and sores in their tails and paws, due to low immunity. This correlates with several human studies that show changes in the immune system of sleep-deprived people. For example, certain cells in our body called natural killer cells, which kill viruses, get reduced in people who don’t sleep properly. Consequently, the commonest of coughs and colds could ravage our body if we haven’t got enough sleep.
Not sleeping could actually be counter-productive to work—even a little less sleep has been shown to decrease cognitive function and coordination of tasks. In fact, a study conducted last year showed that ‘sleeping on it’ increased the ability to establish connections and links—what we call lateral thinking.
What happens when you sleep
Sleep is actually an active time for the body, and the ‘daily servicing’ time that your body needs to function efficiently. Unwittingly, however, modern life seems to revolve around stuff that prevents sleep. Caffeine, of course, is one of the best known, but carbonated drinks also contain it, as do dark chocolate, cocoa and even some cold medications.
Alcohol could also keep you up at night. Although it initially acts as a sedative, alcohol has been shown to disrupt both the length, sequence and the time taken to fall asleep. It probably does so by messing up the function of two brain chemicals called serotonin and norepinephrine, both important regulators. If you like to smoke and drink, all the worse—nicotine is another stimulant.
Insomnia could also be the unintended side effect of certain drugs such as theoflin, taken for asthma. Diet pills too could have this impact.
For those who are not trying to lose weight, insomnia could be the consequence of a heavy meal just before bedtime. Too much protein in the food could keep you up—it is likely to have high portions of an amino acid called tyrosine, which acts as a stimulant. Heavy, spicy food could also cause heartburn and wake you up in the middle of the night.
Good old-fashioned advice, such as sleeping in totally dark rooms, could actually work after all. So could a glass of warm milk. Apparently, milk has a sleep inducing chemical called tryptophan.
(Write to us at firstname.lastname@example.org)