The link between sensitivity, stress and hair loss. Part I: The theory
Can a sensitive scalp lead to hair loss? This question crossed my mind when I noticed my hair loss returning to normal after addressing scalp sensitivity. Let’s take a closer look at this connection.
Last year, I was completely dissatisfied with my hair, so I decided to cut it shorter. I started 2024 with the shortest haircut I’ve ever had (shoulder length). Why, you ask? Despite having great hair products and a solid routine, the reason was simple yet unfortunate—hair shedding.
Photo by Oliver Hihn
Throughout 2023 and into early 2024, I struggled with mild hair shedding. In my case, the main triggers were stress and scalp sensitivity. One issue fueled the other, and together, they ultimately led to hair loss. It wasn’t severe, but the ends still needed an occasional trim. Nevertheless, I was thrilled to see baby hairs growing, healthy ends, and minimal hair loss by summer 2024:
First attempts to overcome shedding
The key to my success was recognizing that stress and sensitivity are interconnected and both contribute to hair loss.
Firstly, I decided to consult a dermatologist, complete blood tests, and consider other potential health issues that might trigger hair loss. The dermatologist diagnosed me with telogen effluvium. In my case, this meant I was experiencing gradual hair shedding as a result of stress/ unknown factors (other potential diagnosis were ruled out through blood work and a review of my medical history).
My second thought was to tackle the stress factors—and so I did: meditation, healthier eating habits, outdoor activities, and other stress-relief strategies. However, my hair still didn’t stop its gradual shedding…
Sensitive scalp: definition
That’s when I began documenting all my hair-washing routines. Before long, I noticed a pattern: whenever my scalp wasn’t itchy or burning, my hair shedding would return to normal. This realization led me to experiment with products designed for sensitive scalps. I eliminated shampoos that triggered a burning sensation and started using more moisturizing masks specifically designed for the scalp.
I delved into scientific articles and studies to validate my thoughts and support the connection between sensitivity and hair shedding. But first, lets determine what it means:
Sensitive scalp is a condition when subjective symptoms such as pain, burning, itching, and redness are triggered by chemical factors (air pollution, water quality, ingredients in cosmetics), emotional stress, hormonal imbalance, or physical factors (weather conditions).
Now, let’s dive into the theory! I want to start with the: “Sensitive scalp: An epidemiologic study in patients with hair loss“, 2022:
The study's primary goal was "to determine the prevalence of sensitive scalp in patients with trichological disorders." However, the most groundbreaking discovery was the strong connection between sensitive scalp and sensitive skin on the body:
“Sensitive scalp is probably one of the manifestations of sensitive skin, since most of these patients declare to have sensitive skin in another body area. Predisposing factors may be either a history of atopic dermatitis or greasy/dry scalp and an associated factor may be current hair loss.“
The study was conducted “on patients of the Dermatology Clinic of Genova from January 2018 to September 2019 for scarring and non-scarring alopecias”. Don't be intimidated by the term "alopecia"—it's simply the scientific name for a condition where hair falls out more than usual. So, the patient pool was wide - telogen effluvium (TE); androgenetic alopecia (AGA); alopecia areata (AA); scarring alopecia (SA); trichotillomania (TR - a chronic condition where a person compulsively pulls out their hair.). Furthermore, scalp symptoms such as pruritus, pain, burning, and itching sensations, both localized and across the entire perimeter of the scalp, were documented.
A total of 317 individuals of various ages and genders participated in the study, each diagnosed with one or more of the conditions mentioned above. Patients with telogen effluvium (TE) reported the highest number of complaints about scalp sensitivity (at this point I felt like shouting, “That’s me!”) — ranging from mild pain to a burning sensation. Other patients did not have such severe reactions.
For instance, the group with androgenetic alopecia (AGA) reported complaints of itching and dandruff, which were occasionally accompanied by seborrheic dermatitis but not by scalp sensitivity or reactivity.
102 out of 317 had sensitive skin (mainly women). Although, why women prevail “is unclear, but they may have an increase in pain perception related to higher anxiety scores than men“. So this is where the stress factor comes into play.
Furthermore, as we age, the scalp tends to become more sensitive. This might be “related to the loss of nerve endings in the epidermis due to age and to the chronic use of irritants in shampoos. Cosmetic and care products may unbalance scalp microbiome inducing immunological or inflammatory responses.“ (This is when I decided I wouldn’t be using shampoos or masks on my scalp that cause itching or a burning sensation anymore. Who wants to damage their nerve endings, right?)
People experiencing hair loss are more likely to have a sensitive scalp. When you add stress into the mix, it can gradually intensify hair shedding.
Inflammation, dermatitis and scalp sensitivity
I began reflecting on hair sensitivity and found that inflammation in the hair follicles is a common factor in most cases of hair loss. The Spanish company Pharma Hermetic, known for developing various hair loss treatments, discovered during their studies that: “Interleukin 6 (IL6) is an inflammatory cytokine, which is present in most hair loss cases. When the hair starts to fall out the level of IL6 rises in concentration and inactivity. The inhibition of IL6 near the hair follicle area has been the main focus of medicinal treatment for many years”.
That's why reducing inflammation and calming skin reactivity could help normalize hair loss.
The following studies support this idea. An interesting article from 2012: “Sensitive Scalp” revealed that patients with atopic dermatitis experience sensitivity more frequently. Stress and climate changes were also identified as contributing factors:
It’s challenging to distinguish between sensitivity and atopic dermatitis, but hair loss can trigger or worsen both conditions.
A 2002 study titled: "Sensitive Skin Is Not Limited to the Face" explores skin sensitivity as a whole, highlighting that it affects more than just the face. The authors reviewed patients from a dermatology clinic to better understand the prevalence and characteristics of sensitive skin:
The majority of participants—85% of 400 patients—reported that their skin was prone to sensitivity, with the hands, scalp, and legs being the most reactive areas. According to statistics, more than 50% of Europeans are prone to reactive skin.
Urban environment as a triggering factor
But what causes this discomfort? Where does it come from, aside from the initial triggers like dermatitis and allergies? Unfortunately, there are many other factors that can contribute to it. In this context, it’s interesting to refer to the 2023 article: “Review of Factors Influencing Sensitive Skin: Focus on Urban Environments”:
Since most of us live in cities, it’s essential to consider the factors that provoke excessive skin reactivity in urban environments. Today, around 37% of the population experiences sensitivity issues, and this number continues to grow due to high stress levels and worsening environmental conditions. The study highlights urban living as one of the key triggers for increased sensitivity.
The etiology of sensitive skin “remains elusive, potentially involving sensory nerve dysfunction, heightened vascular reactivity, barrier impairments, and immune-inflammatory mechanisms of the skin. Additionally, the surge in sensitive skin cases is associated with environmental pollution and unhealthy lifestyles“.
The study found a direct link between elevated stress levels and heightened skin discomfort. The stress often leads to sleep disturbances, which in turn contribute to transepidermal water loss, compromising the skin’s barrier integrity. And with that, irritation is quick to make its appearance.
The study examines other important factors, namely:
Hormone levels—especially fluctuations in estrogen.
Spices - especially capsaicin from chili peppers which activates the TRPV1 receptor, which in turn “stimulates the release of neuropeptides and excitatory amino acids from free nerve endings, ultimately leading to the sensation of pain in the cerebral cortex“.
Cosmetic products – frequent and simultaneous use of multiple products can thin the stratum corneum, especially when combined with aggressive or inadequate cleansing. It can be difficult to identify which product is causing sensitivity, so the best approach is to test products one at a time.
Smoking - “can disrupt the homeostasis of the epidermal permeability barrier” or impair its function.
Alcohol consumption - the “decomposition of ethanol into acetaldehyde induces vasodilation, leading to facial burning and flushing“, which can increase sensitivity.
Physical exercise - it’s not as straightforward as it seems. While physical activity can cause temporary redness due to increased blood flow, it rarely results in long-term discomfort. In fact, regular exercise helps lower stress levels, which has a positive impact on overall skin health and can actually reduce sensitivity and reactivity.
Environment features - sun rays thin the skin, the integrity of the epidermal barrier becomes damaged, the level of moisture decreases and the skin becomes more susceptible; temperature and humidity - temperatures exceeding 43°C activate the already known to us TRPV1 receptor, which "leads to a sensation of heat and pain." Changes in temperature and humidity are provoking factors, but it is low humidity that is more likely to cause discomfort; air pollution - micro-sized dust particles can disrupt the skin barrier to varying degrees and can exacerbate existing inflammation.
Let’s take a closer look at the table. It outlines the key factors influencing reactivity, which we touched on earlier:
Researchers conclude that increased reactivity is influenced by various internal and external factors. The urban environment plays a significant role in triggering reactivity—factors like pollution, stress, and lifestyle can disrupt the epidermal barrier, either individually or in combination. When a genetic predisposition is present, the likelihood of adverse reactions rises. For instance, genetic variations in the 2p21 region have been identified in the Han population, further increasing susceptibility to these reactions.
Based on this study, we can conclude that inflammatory skin reactions and emotional stress are directly linked to skin sensitivity.
Conclusion
While researching, I was amazed by the sheer number of factors that can affect scalp and trigger hair loss. Many studies on this topic, consistently point to the same recurring cycle—what we might call the "Wheel of Samsara": sensitivity, hair loss, and stress. It doesn’t really matter which factor sets the wheel in motion; what’s clear is that it’s they all are connected. ButI think there’s always a way to break the cycle and find solutions.
In the next article, I want to share my personal hair care routine, tips and products that have helped me manage sensitivity and reduce hair shedding. See you soon and hope this was helpful!