Why Our Skin Feels ‘Tight’ After Using Facial Cleanser
Researchers from Stanford University have revealed the process responsible for the sensation of skin tightness that occurs after cleansing and the subsequent relief provided by moisturizing. Their findings, presented in PNAS Nexus, illustrate how alterations in the skin’s outermost layer contribute to these sensations.
Leveraging their discoveries, they created a predictive model that closely aligned with feedback from human trials. This study not only opens up fresh opportunities for the development of skincare products but also suggests potential applications in wearable technology capable of detecting and communicating mechanical skin changes.
Exploring Skin Sensations
As we cleanse our facial skin, it can sometimes take on a tight sensation, which is often alleviated when we apply our preferred moisturizer. While this perception of our skin may appear to be a matter of personal interpretation, Stanford researchers have recently unveiled the underlying mechanism behind these sensations.
Their research, which has been published today, September 26, in PNAS Nexus, elucidates how alterations in the external layer of our skin lead to sensory experiences and offers a quantitative method for gauging how individuals will perceive the condition of their skin following the use of moisturizers or cleansers.
Reinhold Dauskardt, the Ruth G. and William K. Bowes Professor in Stanford’s Department of Materials Science and Engineering, stated, “This study furnishes a fresh comprehension of how products impact the physical attributes of our skin, encompassing not only skin health but also our sensory perception of it. This marks a significant advancement, providing an entirely new perspective on formulating these products.”
Mechanism and Testing
Our skin, being the body’s largest organ, serves as a vital barrier against external elements. The outermost layer, the stratum corneum, guards against unwanted substances and maintains moisture within. Harsh cleansers can strip away the lipids that retain moisture, causing the stratum corneum to contract. Conversely, effective moisturizers enhance the stratum corneum’s water content, prompting it to expand.
Dauskardt and his team hypothesized that the mechanical effects of this contraction and expansion travel through the skin to reach mechanoreceptors, which are sensory receptors converting mechanical forces into neurological signals beneath the epidermis. These signals then relay to the brain, resulting in the perception of skin tightness.
To validate their theory, the researchers examined the impact of nine diverse moisturizer formulas and six different cleansers on donor skin samples from three body locations: the cheek, forehead, and abdomen. They assessed stratum corneum changes in the laboratory and employed an advanced model of human skin to predict the signals transmitted to the mechanoreceptors.
Regarding the sensory perception of the skin, Dauskardt clarified that they effectively ranked the different formulations.
Their predictive analysis closely paralleled the results from human trials, where 2,000 women in France assessed the nine moisturizers, and 700 women in China evaluated the six cleansers, sharing their experiences of skin tightness after product application.
Dauskardt stressed, “Our predictions closely matched what participants reported, demonstrating a remarkable correlation with significant statistical validity.”
Fostering Innovation
This ability to foresee how individuals will feel following skincare treatments could assist cosmetics companies in enhancing their products before conducting human trials. Furthermore, Dauskardt emphasized that their comprehensive model of how mechanical stress travels through skin layers has the potential to be applied beyond just evaluating tightness.
He explained, “This provides a framework for the development of innovative products. If you’re altering the outer skin layer in ways that impact its strain and stress, we can predict how that information will be transmitted and perceived by consumers.”
Dauskardt is also exploring the potential use of this newfound knowledge in developing wearable devices. By understanding how our brains interpret subtle changes in skin tension, we could potentially use this mechanism to convey intentional signals. Just as people reading braille translate tactile sensations on their fingertips into words, a device capable of creating small mechanical shifts on our skin might transmit information.
Dauskardt
Dauskardt explained, “What we’ve achieved is uncovering how mechanical information travels from the outermost stratum corneum layer to the deeper skin layers containing neurons. So, the question arises: can we establish communication through human skin? Can we create a device that conveys information to someone without relying on words or visuals, leveraging our understanding of these mechanisms? This is an area of great interest for us.”
Reference: “Sensory neuron activation from topical treatments modulates the sensorial perception of human skin” by Ross Bennett-Kennett, Joseph Pace, Barbara Lynch, Yegor Domanov, Gustavo S Luengo, Anne Potter, and Reinhold H Dauskardt, published on September 26, 2023, in PNAS Nexus.
DOI: 10.1093/pnasnexus/pgad292
Dauskardt holds affiliations with Stanford Bio-X, the Cardiovascular Institute, the Wu Tsai Human Performance Alliance, and the Wu Tsai Neurosciences Institute, and is associated with the Precourt Institute for Energy and the Stanford Woods Institute for the Environment.
Read the original article on: Scietech Daily
