The brain in our skin: An interview with Dr. Claudia Aguirre

Mar 19, 2020

 Dr. Claudia Aguirre has a Ph.D. in neuroscience from USC and travels the world lecturing on a broad range of topics from neuroscience to skin care, and “everything under the wellness umbrella.” 

Her work has focused on longevity—from the aging brain to aging skin. She is a TEDx speaker, TED Ed educator, and international scientific consultant and advisor in the health and wellness industries. She’s interested, she says, “in extending the health of our mind and body.”

Dr. Murad: What do you mean by “the hidden brain in your skin”?

Dr. Claudia: I mean that the skin is highly innervated and intricately connected to the brain and central nervous system, just as other sensory organs are. We’re discovering that the skin has a lot of neuro potential, or neuroplasticity, that has gone unrecognized. For example, just as our eyes have receptors that transduce light photons into signals to the brain that we process as vision, we’re discovering that our skin also has light receptors. Although we don’t yet know how they work, we speculate that they might be signaling the brain to make systemic changes that affect the full nervous system. Similarly, we’re also discovering that we have olfactory receptors in the hair follicles, just as we do in the nose. Why they are there and how they work remain a mystery, but the more we learn, the more we realize how important the skin is.

Another example is touch—for which our skin is the primary sense organ. Skin is also our largest organ, which gives you a clue as to how important touch is. Different receptors in the skin can tell us not only whether what we touch is hot or cold, rough or smooth; it can even sense the intention behind the touch. A gentle touch feels much different than an aggressive one. We can tell whether the person giving us a massage is paying attention or whether they’re distracted. Moreover, different kinds of touch elicit different biochemical and hormonal responses, which have systemic results. A hug or kiss stimulates the release of oxytocin, the bonding hormone, through the bloodstream, while a punch or shove will release adrenaline and cortisol.

All of these capabilities are what I mean by the hidden brain in the skin.

Dr. Murad: How does Cultural Stress impact the skin?

Dr. Claudia: The skin is connected to the nervous system; it’s connected to the endocrine system. The skin is impacted by our emotional states and, conversely, our skin can impact how we feel about ourselves. Cultural stress and anxiety can trigger or aggravate many skin conditions—from acne to eczema to herpes, psoriasis, and rosacea. Conversely, a disfiguring skin condition can trigger stress, anxiety, depression, and even suicide. Chronic, generalized anxiety can create chronic inflammation and exacerbate inflammatory skin conditions, such as those I mentioned previously. Chronic stress can result in chronic anxiety, hypervigilance, poor sleep, and a whole cascade of effects resulting in a constant breakdown of tissues and organs, including the skin. There’s a whole new field of medicine being developed called psychodermatology, which is the study and treatment of the psychological component of skin conditions. Better understanding of the neuropotential of skin also opens the possibility of whole new avenues of treatment for many of our chronic conditions—through the skin! For example, what if we could affect changes in blood pressure through the nitric oxide system of the skin? Wouldn’t it be amazing if we could apply something topically that would reduce blood pressure, freeing people from having to take statins, which have side effects?

Dr. Murad: How did you decide to apply your training as a neuroscientist to dermatology?

Dr. Claudia: I was looking for a career outside of academia and wanted to bring neuroscience into a field where it isn’t typically applied. When I finished my Ph.D. at USC, I started looking for alternative careers. I met the founders of Dermalogica, whom you know very well, and we both took the leap of hiring a neuroscientist to develop a line for sensitive skin. Since then, I’ve understood that neuroscience should absolutely be part of the conversation about skincare and beauty because the brain and the skin are intimately connected and I’ve worked with many leading skincare companies, including, Murad, as you know. Skincare is important not only for the skin, but also the brain.

Dr. Murad: The closing line of your UCLA TedX talk is “Listen to your skin.” What are some of the things we should listen for?

Dr. Claudia: You should listen for all the little signs that your skin tells you that you tend to ignore. You get a rash, and you brush it off: “Maybe it’s just dry out. Maybe I need to switch shampoos.” But if it occurs repeatedly, you need to look more closely and ask, “What could my skin be trying to tell me?” Are you repressing emotions? Is there a relationship issue you’re avoiding? Is there some other life circumstance that’s “gotten under your skin”? The body has a wisdom we should listen to. When we do, we’re more likely to uncover the root cause of what ails us.