It is often said that we are sleeping way less than what we should and that lack of sleep can cause weight gain, depression and reduced fertility. However, according to the findings of a new study, our ancestors may have got less sleep than we do.
Researchers in the United States have studied the sleeping patterns of traditional societies in Africa and South America, whose lifestyles closely resemble ancient hunter gatherers. They monitored 98 people for 1,165 nights. According to the findings, these people slept for an average of 6.5 hours each night. On the other hand, people in the US on average sleep for about 7 hours as per the findings of a poll.
Prof Jerome Siegel from the University of California, Los Angeles says, “These groups, which are rapidly disappearing, give the last opportunity to really know what human sleep was like before we all created our various civilizations. What is absolutely clear is that they don’t sleep more than we do”.
The researchers discovered that surprisingly, natural light did not have a big influence. Most people fell asleep on average 3.3 hours after sunset. But temperature played an important part. “What we saw was quite striking – that sleep is occurring during this period of falling temperature and when the temperature hits bottom, they wake up”, said Prof Siegel.
Commenting on the research, Prof Derk-Jan Dijk, from the Surrey Sleep Research Centre at the University of Surrey, UK, said that it was an important study. “I think we need to re-evaluate the timing of our social schedules, including work, relative to the natural environment. Our social environment has an impact on when we decide to go to sleep and wake up”.