Beauty Sleep: The Science Behind Sleep and Skin Health

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We all want to have great skin. It boosts our self-confidence, and frankly, just makes us feel better when we see ourselves in the mirror every morning. However, maintaining healthy skin often takes a backseat to other pressing demands of daily life, such as work, family, and social obligations. While many of us invest in skincare products, routines, and treatments, we often overlook one of the most fundamental components of skin health: the quality and quantity of our sleep. Sleep is not just a period of rest for the mind and body; it's a crucial time when the body undergoes repair and regeneration, directly affecting the skin's appearance and resilience.

Research shows that the relationship between sleep and skin health is far-reaching, with significant implications for those seeking to maintain a youthful and radiant complexion. For instance, a study found that participants who slept for 7-9 hours per night exhibited 30% greater skin barrier recovery compared to those who slept for only 5 hours or less. This may be because, during deep sleep stages, blood flow to the skin increases , which helps to deliver essential nutrients and oxygen necessary for skin repair. Furthermore, another study revealed that chronic poor sleep quality is associated with increased signs of intrinsic aging , such as fine lines, wrinkles, and uneven skin tone, diminished skin barrier function, and lower satisfaction with appearance. Inadequate sleep also impairs the body's ability to balance hydration levels, resulting in dull, dry skin and more pronounced under-eye circles. Therefore, prioritizing quality sleep is not just about feeling refreshed; it’s an essential step towards achieving and maintaining healthy, glowing skin.

At the core of the connection between sleep and skin health is the hormone cortisol, commonly known as the "stress hormone." Cortisol naturally fluctuates throughout the day, peaks in the early morning, and declines throughout the day. When one has inadequate sleep, cortisol levels rise which can induce inflammation prevent you from maintaining a healthy and youthful skin complexion. What’s more, high cortisol levels can accelerate the breakdown of collagen —a protein responsible for skin's firmness and elasticity. Elevated cortisol can lead to a slowdown in skin cell renewal , causing a duller, less vibrant appearance.

A 2017 study underscored these findings, showing that individuals with poor sleep quality exhibited significantly higher levels of transepidermal water loss (TEWL), i.e. the amount of water that evaporates from the skin into the air. Higher TEWL indicates a weakened skin barrier that is less effective at retaining moisture, leading to dryness and increased susceptibility to environmental stressors like pollution and UV radiation. High TEWL can make the skin more prone to damage and aging. Sleep-deprived individuals often experience increased oxidative stress in the skin, which can lead to the breakdown of important skin proteins and accelerate the aging process. This imbalance between free radicals and antioxidants, combined with the reduced repair capacity during sleep deprivation, can significantly impact the skin's ability to maintain a healthy, youthful appearance.

Quality sleep, therefore, serves as a natural "reset" for the skin. During sleep, the body ramps up blood flow and collagen production, both of which are critical for maintaining skin elasticity and firmness. Research revealed that even a short period of sleep deprivation (31 hours) resulted in noticeable skin changes. Participants in the study were observed to have increased fine lines and wrinkles. More strikingly, sleep-deprived individuals were perceived by others as looking more fatigued, less healthy, and less attractive compared to their well-rested counterparts. This highlights how sleep quality directly affects both the physical properties of the skin and how others perceive us. It seems that beauty sleep really is a thing.

The effects of sleep debt on skin health extend to the immune system and wound healing processes as well. A study found that even partial night sleep deprivation resulted in a significant reduction in natural killer cell activity, a crucial component of the immune system. This impaired immune function can lead to increased susceptibility to skin infections and delayed wound healing. Sleep deprivation also impairs collagen deposition , a critical factor in wound healing.

Sleep quality can significantly impact existing dermatologic conditions , such as acne, eczema, psoriasis, and rosacea. Poor sleep can exacerbate these conditions by increasing inflammation and stress hormone levels, like cortisol, which can trigger flare-ups or worsen symptoms. For example, eczema sufferers often experience heightened itching and irritation due to disrupted sleep, while psoriasis patients may see an increase in plaques and lesions.

The importance of sleep extends far beyond just feeling rested; it is a vital component of maintaining healthy, vibrant skin. From promoting skin repair and regeneration to reducing inflammation and supporting the immune system, adequate sleep plays a central role in every aspect of skin health. Neglecting sleep can accelerate aging, exacerbate existing skin conditions, and diminish the effectiveness of even the best skincare routines. As such, achieving quality sleep should be considered a fundamental step in any skincare regimen. By prioritizing restful sleep, we can help preserve our skin's natural beauty, resilience, and youthfulness for years to come.

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About the author

Alen Juginovi? is a medical doctor and postdoctoral researcher in the Department of Neurobiology at Harvard Medical School studying the effect of poor sleep quality on health. He is a member of the Editorial Board of the Journal of Clinical Sleep Medicine, the official journal of the American Academy of Sleep Medicine. As a keynote speaker at conferences and teacher at Harvard College, he often discusses sleep's importance in media appearances. Alen is also focused on personalized sleep optimization for individuals and athletes. He leads a team at Med&X Association organizing international award-winning conferences, including the Plexus Conference , which drew over 2,400 participants from 30+ countries, featuring 10 Nobel laureates and medical leaders. Med&X also partners with research labs and clinics from leading universities and hospitals around the world offering invaluable internships to help accelerate the development of top medical students, physicians and scientists. Feel free to contact Alen via LinkedIn for any inquiries.

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The writer has made good faith efforts to confirm that all sleep science, research or health statistics referenced from third party sources are accurately represented. However, no warranty is made as to completeness or ongoing accuracy. Readers agree any reliance on newsletter content for decision making is at their sole discretion and risk. The writer is released of liability or claims related to applied use of this general educational content on sleep physiology or best practices.