Neurocosmetics and the Brain-Skin Axis: Sleep Deprivation 

I had a colleague so interested in biochemical mechanisms connected to the biological phenomena, that one day I jokingly said: “If somebody tells you that there is a cow flying over Manhattan, will you ask ‘by what mechanism?’” Indeed, studying mechanisms is the next step after a phenomenon has been tested in controlled experiments. Looking for mechanisms of poorly described phenomena would have prompted my post-doctoral advisor to say: “Do not waste clean thoughts on dirty results.”

This recommendation should be held as a golden guideline in skin care, where too often results obtained with cultured cells or with laboratory rodents are considered as if they originated from clinical testing. The interpretation of non-homogeneous data can lead to illegitimate conclusions and perhaps to the use of inappropriate ingredients.

This is even more true when considering the effects of psychological stress on skin.

Psychological Stress and Skin

It is common knowledge among laypersons that people under stress have “poor” skin. Fine. That can be the beginning of an epidemiological study. And yet, what do we mean by stress? And, in particular, what do we mean by psychological stress? Is the psychological stress experienced by a gambler similar to the stress provoked by an abusive partner? How can we design controlled experiments to study the effect of psychological stress on skin?

One way is to study the cutaneous effect of the stress provoked by sleep deprivation, a parameter that can be easily quantifiable. Sleep deprivation, indeed, can be chronic, transient or acute, and we have the tools to measure physiological and biophysical skin parameters.

Chronic sleep deprivation occurs in people called “poor sleepers” who sleep a few hours per night, and the control is offered by “good sleepers” who sleep seven to eight hours a night. Good sleepers and poor sleepers were analyzed by an expert panel for aging scores and were also tested for Transepidermal Water Loss (TEWL) before and three days after tape stripping as well as for recovery from erythema one day after exposure to UV radiation. Good sleepers had significantly lower intrinsic skin aging scores. At baseline, poor sleepers had significantly higher levels of TEWL. At 72 hours after tape stripping, good sleepers had 30% greater barrier recovery compared with poor sleepers. At 24 hours after exposure to UV, good sleepers had significantly better recovery from erythema. Good sleepers also reported a better perception of their appearance and physical attractiveness compared with poor sleepers.¹

The effects of transient sleep deprivation can be studied in controlled experiments; for instance, by having subjects sleep eight hours per night for six nights in week one and four hours per night for six nights in week two and comparing the results so that every panelist serves as her own control. The study included 32 Korean women about 40 years of age and sleep time was individually monitored by smartwatches. Skin hydration was significantly reduced after one day of sleep deprivation, and it continued to decrease. Skin gloss, desquamation, transparency, elasticity and wrinkles were significantly aggravated after 1 day of sleep deprivation. Skin texture was significantly aggravated on the fourth day of sleep restriction. The authors made it clear that elasticity was most affected by reduced sleep.²

The cutaneous effects of acute sleep deprivation were measured on five women and five men photographed at 2:30 p.m. after one night of normal sleep and after 31 hours of sleep deprivation following a night with five hours of sleep. The pictures were analyzed by a panel of 20 experts. Sleep deprived individuals had more hanging eyelids, redder eyes, more swollen eyes, darker circles under the eyes, paler skin, more wrinkles/fine lines and more droopy corners of the mouth. The ratings of fatigue were related to glazed eyes and to all the cues affected by sleep deprivation. Rash/eczema were not significantly affected by sleep deprivation. In addition, sleep-deprived individuals looked sadder than after normal sleep, and sadness was related to looking fatigued³.

What About the Mechanisms?

Glen Rein made a major contribution by reviewing a large number of papers relative to the effect of neuropeptides in the skin.⁴ The data indicated that neuropeptides released by neural endings in the skin, induce the synthesis of I-CAM 1 and trigger an inflammatory response. This provokes oxidative stress, release of proteinases and fiber digestion and disorganization in the dermis, thus accelerating the accumulation of damage and therefore the rate of skin aging. A recent paper by Bobok and Taskesen⁴ provides a thorough update in this field. One of the interesting results from the sleep deprivation studies is that sleep deprivation remarkably affects skin elasticity,² as it is expected when pro-inflammatory agents are released in the skin.

Conclusion

The Brain-Skin Axis is at work in both directions, and during periods of psychological stress, the brain releases hormones like cortisol and corticotropin-releasing hormone and a plethora of neuropeptides that are found in the skin.^4,5 These molecules trigger oxidative stress and exacerbate inflammatory conditions like eczema, psoriasis and acne, while slowly disorganizing the network of dermal elastic fibers.

This is not to say, though, that interventions to fight the cutaneous effects of psychological stress must be oriented towards the use of psychotropic substances to inhibit the very release of hormones and neuropeptides! In a study with cultured human amnion fibroblasts, it was shown that the addition of cortisol provoked collagen digestion⁶, and this observation is of importance for the rupture of the amniotic membrane and parturition…and not to recommend inhibiting the release of cortisol to avoid collagen degradation in the skin!

Paolo Giacomoni, PhD

Insight Analysis Consulting
[email protected]

Paolo Giacomoni acts as an independent consultant to the skin care industry. He served as Executive Director of Research at Estée Lauder and was Head of the Department of Biology with L’Oréal. He has built a record of achievements through research on DNA damage and metabolic impairment induced by UV radiation as well as on the positive effects of vitamins and antioxidants. He has authored more than 100 peer-reviewed publications and has more than 20 patents. He is presently Head of R&D with L.RAPHAEL—The science of beauty—Geneva, Switzerland.

References

1. Oyetakin-White P, Suggs A, Koo B, Matsui MS, Yarosh D, Cooper KD, Baron ED. Does poor sleep quality affect skin ageing? Clin Exp Dermatol. 2015 Jan;40(1):17-22. doi: 10.1111/ced.12455. Epub 2014 Sep 30. PMID: 25266053.
2. Jang SI, Lee M, Han J, Kim J, Kim AR, An JS, Park JO, Kim BJ, Kim E. A study of skin characteristics with long-term sleep restriction in Korean women in their 40s. Skin Res Technol. 2020 Mar;26(2):193-199. doi: 10.1111/srt.12797. Epub 2019 Nov 6. PMID: 31692145
3. Sundelin T, Lekander M, Kecklund G, Van Someren EJ, Olsson A, Axelsson J. Cues of fatigue: effects of sleep deprivation on facial appearance. Sleep. 2013 Sep 1;36(9):1355-60. doi: 10.5665/sleep.2964. PMID: 23997369; PMCID: PMC3738045.
4. Giacomoni, PU. & Rein, G. (2017) Skin Aging: A generalization of the micro-inflammatory hypothesis. In: Textbook of Aging Skin (Farage, Miller, Maibach editors) Springer Verlag pp 1289-1298
5. Bobok N, Taskesen T. Stress-Induced Changes of the Skin: A Narrative Review. Cureus. 2025 Nov 7;17(11):e96285. doi: 10.7759/cureus.96285. PMID: 41362509; PMCID: PMC12681996.
6. Mi Y, Wang W, Zhang C, Liu C, Lu J, Li W, Zuo R, Myatt L, Sun K. Autophagic Degradation of Collagen 1A1 by Cortisol in Human Amnion Fibroblasts. Endocrinology. 2017 Apr 1;158(4):1005-1014. doi: 10.1210/en.2016-1829. PMID: 28323983.