We are all aware that sleep is an important part of the way we look. A sleep-deprived person is marked by a tired-looking face, with dark circles under the eyes and swollen eyelids.
We have already covered the importance of sleep in regulating our ‘internal clock’ or circadian rhythm, which has far-reaching effects on body processes. Let’s take a closer look at the role of sleep in maintaining our skin and understand how poor-quality sleep or insufficient sleep can accelerate our skin’s continuous ageing process.
The role of sleep in skin health and ageing
Though seemingly inactive when asleep, our body is actually doing a lot. When we sleep, our body is very actively repairing itself and preparing for the physical and mental rigour of the following day. For our skin, this encompasses a number of processes:
1] Sufficient sleep helps protect the skin (and other tissue) from damage
Reactive molecules called free radicals, which promote cell and protein damage, play an intrinsic role in the ageing process. Any damage to the skin is repaired when we sleep. Antioxidant defense responses are decreased during sleep deprivation, which inhibits the body’s ability to neutralise these damaging molecules.
2] Blood flow to the skin increases during sleep
This improves the flow of the nutrients our skin requires to maintain its protective barriers that are naturally compromised with age. A compromised skin barrier can make us more susceptible to environmental damage especially from the sun’s UV rays (see photoageing) and also promotes dry skin.
3] Sleep affects the expression of genes in skin cells
Skin cells such as keratinocytes (the cells that make up the top layer of our skin) melanocytes (pigment-producing cells), and fibroblasts (precursor cells) have ‘clock genes’ that are regulated by our circadian rhythms or sleep cycles. The repairability of these cells is switched on or off by these genes depending on our sleep.
4] Sleep affects immunity and the process of inflammation
Sleep plays a role in the development of our immune system’s memory, which directly affects our skin’s ability to protect itself from the environment. Sleep is also important for the regulation of inflammation. Unnecessary or unresolved inflammation can cause damage to healthy skin tissue (causing premature ageing), delay wound healing and worsen conditions such as acne and eczema.
5] Sleep helps regulate hormone levels
Hormones affect the metabolism of skin cells. Disruptions in sleep cause irregular hormone levels, can disrupt metabolism and increase stress on our body. This can affect skin health and interfere with its renewal process. For example, the stress hormone, cortisol, increases with insufficient sleep, which over time increases skin inflammation (and is thought to worsen acne too)
6] Sleep can affect skin protein structure
The sugar from our diet can modify proteins, which are then called Advanced Glycation End products (AGEs). AGEs can also be found in certain foods. They interfere with the repair process of our skin and contribute to ageing. The accumulation of AGEs in our body is thought to be worsened with sleep deprivation and disorders.
These factors could explain why a number of studies have shown associations of ageing with poor sleep:
- Research has linked chronic poor sleep quality with increased signs of intrinsic ageing, diminished skin barrier function and lower satisfaction with appearance. Poor sleepers had higher levels of transepidermal water loss (i.e. skin’s water loss to the environment) leading to dry skin and decreased skin barrier recovery after exposure to UV-light.
- One study showed that even modest sleep restriction (of about 2 hours less) delays wound healing. Supplemental nutrition helps mitigate some issues with local immune responses, but the rate of wound healing remained affected.
- Skin lesions are among the first and most pronounced defects in rats subjected to prolonged sleep deprivation.
- Sleep disturbances have also been linked to eczema, however, it is difficult to differentiate the cause from the effect.
- A study showed that sleep-deprived, tired-looking faces, with dark circles under the eyes and swollen eyelids, are perceived as less healthy and less attractive by others, and affects social interactions.
Taking care of our skin goes far beyond adding a night serum to our night routine. Sufficient sleep is one of the pillars of a healthy lifestyle, and healthy-looking skin is a welcome consequence. These studies are a small testament of a much bigger picture – getting the recommended seven to nine hours of shut-eye can help us look and feel better.
DeMartino T, et al. Sleep 2016; 39(7): 1361-1369.
Isami F, et al. J Int Med Res 2018; 46(3): 1043-1051
Kahan V, et al. Skin Pharmacol Physiol 2014; 27(3): 127-131.
Luyster FS, et al. Sleep. 2012; 35(6): 727-734.
Nomoto K, et al. Anti-Aging Medicine 2012; 9(6): 165-173.
Oyetakin-White P, et al. Clin Exp Dermatol 2015 Jan; 40(1): 17-22.
Smith TJ, et al. J Appl Physiol 1985; 124(1): 190-200.
Sundelin T, et al. Sleep 2013; 36(9): 1355-1360.
Sundelin T, et al. R Soc Open Sci 2017 May; 4(5): 160918.
Tan KC, et al. Sleep 2006 Mar; 29(3): 329-333.
Walia HK, Mehra R.. Int J Mol Sci 2016; 17(5): E654.