Importance of Sleep
What does sleep do for us?
Sleep is a seemingly unproductive natural process that is observed across a wide range of species including worms, flies, and vertebrates such as humans1. Long term sleep deprivation has been linked to an almost inexhaustible list of diseases like obesity, cardiovascular diseases, cognitive impairment, and premature death, just to name a few2,3. Furthermore it also has a direct impact on relative levels of energy throughout the day4. Sleep is a multifactorial process which cannot be simply measured by duration, but must take into consideration other factors like patterning and quality3. Interestingly to note, a lack of sleep has also been found to increase snacking and the consumption of energy-rich foods. Overall there is accumulating evidence that a sleep duration of 7-8 hours per night in adults is associated with the maintenance of good health4.
How can I improve my sleep?
- A 2016 study found that increased intake of protein in middle and elderly aged overweight and moderately obese adults may improve sleep when dieting to lose weight3.
- A 2013 randomised control trial in China containing 80 subjects found that self-relaxation training (e.g. meditation) can improve sleep quality and cognitive functions in the older population5.
- There is not much evidence in the literature supporting that traditional Western sleep promoting foods like chamomile tea or a glass of milk have any effect on sleep6. There is some evidence however, that there is a connection between macronutrients (e.g. carbohydrates) and sleep, but these studies are few and have a small number of subjects. Nutritional deficiencies in magnesium or vitamin B have been found and characterised to impair sleep. Sleep quality has been found to improve in 43 elderly subjects with insomnia after taking a preparation of melatonin, magnesium, and zinc6.
- A fairly intuitive method especially for those who are always stressed and pressed for time is sleeping earlier. Whilst this may not be able to improve the quality of sleep, it can maximise the duration. A fun way of controlling this variable is by recording sleeping patterns.
References
1. Weber, F. & Dan, Y. Circuit-based interrogation of sleep control. Nature 538, 51–59 (2016).
2. Moller-Levet, C. S. et al. Effects of insufficient sleep on circadian rhythmicity and expression amplitude of the human blood transcriptome. Proceedings of the National Academy of Sciences 110, E1132–E1141 (2013).
3. Zhou, J., Kim, J. E., Armstrong, C. L., Chen, N. & Campbell, W. W. Higher-protein diets improve indexes of sleep in energy-restricted overweight and obese adults: Results from 2 randomized controlled trials. American Journal of Clinical Nutrition 103, 766–774 (2016).
4. Chaput, J.-P. Sleep patterns, diet quality and energy balance. Physiology & Behavior 134, 86–91 (2014).
5. Sun, J., Kang, J., Wang, P. & Zeng, H. Self-relaxation training can improve sleep quality and cognitive functions in the older: A one-year randomised controlled trial. Journal of Clinical Nursing 22, 1270–1280 (2013).
6. Peuhkuri, K., Sihvola, N. & Korpela, R. Diet promotes sleep duration and quality. Nutrition Research 32, 309–319 (2012).
