With the influence of modern technology and lifestyle, many people have become more deprived of sleep. People need to sleep at least eight hours according to conventional knowledge, but for the new research, it may not be so. Traditional people actually sleep just less, yet still survive.
A team of researchers from the University of California - Los Angeles concludes that the sleeping habits of modern people have actually increased from that of people in the early times. As supported by the sleeping patterns of three ancient groups of hunters-gatherers living in Tanzania, Namibia, and Bolivia, our ancestors likely did not get eight hours of sleep a night.
In a study of 94 individuals in a course of 1,165 days, researchers found that these groups living in a traditional way - without electricity or any form of technology - are sleeping just less than six and a half hours a night on the average. They are also used to staying up late and rarely take a nap - both of which suggest that they have much worse sleeping habits than people in the city.
"The fact that we all stay up hours after sunset is absolutely normal and does not appear to be a new development, although electric lights may have further extended this natural waking period," says lead researcher Jerome Siegel, professor of psychiatry at UCLA's Semel Institute of Neuroscience and Human Behavior, in the press release.
In addition, these traditional groups also sleep an hour longer in the winter than in the summer. Despite being different in terms of ancestral origins, they all showed similar sleeping outline, suggesting that people in the old times probably had the same. Although the previous conception had always been that modern life has reduced the conventional sleep length, the current analysis implies that such idea is only but a myth. There was this expectation that without modern technology, people may be sleeping more than eight hours. However, these findings were showing that it is not true.
Obesity, which has been reportedly linked to frequent lack of sleep, does not at all manifest in traditional people. These groups even have much lower number of reported cases in high blood pressure and artherosclerosis, as opposed to people in industrialized societies.
Nevertheless, some findings in the study conform to some ideas of modern people. These include the benefits of morning light, consistent body-clock, and a cool sleeping temperature. Sleep time was found more closely linked to temperature than light. The ancient groups all sleep through the coldest time of the night and wake up at a fair temperature in the morning.
With this research, normal people may not need to worry now if they get less than eight hours of sleep a night. As long as they get what they think their body needs, that would just be fine. After all, it still depends on the daily routine that a person follows.
The research appears in the journal Current Biology.