Sleep is important for all aspects of health but in Chinese Medicine, it is particularly important for the Kidneys. The Kidneys are the Yin to Fires Yang and Yin is recuperated through sleep, rest and slowing down. Despite the need for this dynamic balance rest is not necessarily given the value it deserves in or fast paced lives. The following research looks more closely at the ways lack of sleep affects our mental, emotional and physical health and performance.

Study 1: Iliff, J., (2022) Jeff Iliff: One more reason to get a good night’s sleep | TED Talk.

Jeff Iliff’s fascinating TED Talk explains that, unlike the rest of the body, the brain is not served by the lymphatic system. In the rest of the body wastes and toxins are released from the vessels and mopped up by the lymphatic system that takes them away. For a long time, there was little understanding of how the brain performed this vital housekeeping, particularly as the high blood supply and functioning of the brain should mean that it produces proportionally more waste. It turns out that this is one of the vital functions of sleep. During sleep, our brain cleans and detoxes itself. If we don’t get enough sleep waste builds up in the brain and it gets harder to function. (Iliff, 2022)

This is interesting as Chinese Medicine also makes a link between the Kidneys (and therefore sleep) and the brain.


Study 2: Wagner, U., Gais, S., Haider, H., Verleger, R. and Born, J., (2004) Sleep inspires insight. Nature  (Wagner et al., 2004)

This research looked at the effects of sleep on cognitive ability. Sixty-six healthy subjects (aged 18–31 yr) were asked to do tests that involved learning stimulus-response sequences. The test contained a hidden abstract rule that, if noticed, could improve performance. Participants were tested during the day, during the night and in the morning after sleep. Researchers were interested to know if participants were better at noticing the rule with/without sleep.


What they found was that people who conducted the test after sleep were nearly three times more likely to spot the rule.


Participants were significantly more likely to notice the rule in the morning after sleep.

Slowing down in our current culture

In our current Yang biased culture, where we are encouraged to feel that we have to keep constantly striving just to be safe. In this environment slowing down is an act of rebellion.

[Buddhist] “Teachers speak of “sacred idleness”, as an endangered art. Joy needs space and room to emerge. Tasting this inwardly generated joy, born of stillness, has the power to radically alter our relationship with life. We appreciate the moments of happiness and delight that come to us, and deeply know that there is nothing that we can gain, process, or achieve that can offer the same depth of joy that is inwardly born, not dependant on ideal conditions.” (Feldman, 2017, p.88)


Feldman, C., (2017) Boundless Heart: The Buddha’s Path of Kindness, Compassion, Joy, and Equanimity. Boulder, Colorado: Shambhala Publications Inc.

Iliff, J., (2022) Jeff Iliff: One more reason to get a good night’s sleep | TED Talk. [online] Available at: [Accessed 19 Sep. 2022].

Wagner, U., Gais, S., Haider, H., Verleger, R. and Born, J., (2004) Sleep inspires insight. Nature, 4276972, pp.352–355.