Dr. Daniel Lieberman from Harvard University has denied the common advice about getting a good night's rest by sleeping at least eight hours, stating that "people actually do better if they sleep for seven hours." In an episode of the podcast "Diary of a CEO," he explained that "the idea that you need eight hours of sleep has been around for a long time, primarily since the Industrial Revolution." He elaborated, "My colleagues in evolutionary medicine have put sensors on people who do not have all the factors we've been told destroy sleep. We have been told that television, lights, our phones, and all these things prevent us from sleeping. When you put sensors on people who do not have electricity, do not have televisions, no phones, or any of these devices, it becomes clear that they sleep six to seven hours a night, and they do not take naps." He continued, "So the idea that normal humans sleep eight hours a night is just nonsense. That is not true." He mentioned that reducing screen time may lead to needing less sleep in the long term.
According to the CDC guidelines, children aged 6 to 12 need 9 to 12 hours of sleep per night, while teenagers need 8 to 10 hours. However, an increasing body of research supports Dr. Lieberman’s theory. Lack of sleep has always been associated with chronic health issues such as heart disease, kidney disease, high blood pressure, diabetes, stroke, obesity, and depression. Nonetheless, there are some caveats to the seven-hour rule. For a good night's sleep, the American Academy of Sleep Medicine recommends going to bed at the same time every night and waking up at the same time every morning, even on weekends.
