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In recent years, more and more people have reported skin discomfort in response to common stimuli: redness, tingling, stinging, or the feeling that their skin is “tight.” But what makes the skin suddenly so reactive? Understanding the causes of increased skin sensitivity is the first step toward caring for it properly.
Studies conducted in Europe indicate that a very large proportion of the adult population—predominantly women, but with significant percentages among men as well—report having sensitive skin. This is a growing phenomenon linked to environmental, cosmetic, psychological, and genetic factors.
Skin barrier dysfunction
The skin barrier is the first line of defense: a system made up of lipids, keratinocytes, and proteins that protects against external agents and regulates water loss. When it is damaged, the skin becomes more permeable and more vulnerable to irritants.
Washing too frequently with harsh cleansers, sudden climate changes, or dermatological conditions such as atopic dermatitis can compromise its integrity. In people with atopic skin, barrier dysfunction is considered the central mechanism underlying skin sensitivity.
Environment and climate
The environment we live in has a significant impact. Low temperatures, wind, fluctuating humidity, sun exposure, and air pollution can all destabilize the skin’s balance.
Pollution, in particular, has been associated with an increase in pro-inflammatory particles on the skin’s surface: chronic exposure to fine particulate matter (PM2.5) promotes irritation and redness, altering the hydrolipidic film and the microbiome.
Stress: an invisible but real cause
Psychophysical stress alters hormonal and neurocutaneous balance, contributing to hypersensitivity. Cortisol compromises the lipid barrier and reduces local immune defenses, making inflammatory reactions more likely. Research has documented a higher incidence of skin symptoms—redness, tingling, and flaking—in people experiencing prolonged periods of anxiety.
This is the field of neurocosmetics, which specifically studies the dialogue between the nervous system and the skin.
Hormonal factors
Fluctuations linked to the menstrual cycle, pregnancy, menopause, or endocrine disorders influence the skin’s response. The decrease in estrogen during menopause, for example, reduces collagen and lipid production, making the skin thinner and more prone to dehydration: a very high proportion of women develop signs of skin sensitivity during the first few years after menopause.
Genetics and individual predisposition
People with fair skin or a family history of atopic dermatitis, allergies, or rosacea are more likely to develop skin reactivity. Genetic analyses have identified mutations in the FLG gene (filaggrin) as predisposing factors because they directly affect the structure of the epidermal barrier.
Inadequate cosmetics
Some ingredients—denatured alcohol, fragrances, and certain preservatives—are known sensitizers. A significant proportion of people with sensitive skin report having reacted negatively to a product used in their daily routine.
Layering too many powerful active ingredients—exfoliating acids, retinoids, and vitamins in unstable forms—can also cause pH imbalance and inflammation. For guidance on how to choose ingredients mindfully, see the cosmetic ingredients guide.
Pre-existing skin conditions
Some chronic conditions make the skin more vulnerable. Rosacea is associated with a lower sensory threshold; psoriasis and seborrheic dermatitis alter both the skin structure and the microbiome, increasing reactivity. To distinguish between the different forms of redness, the article on erythrosis, couperose, and rosacea explains the differences.
Allergic reactions and contact dermatitis
Allergic contact dermatitis affects a significant proportion of the European population. These reactions, often caused by nickel, fragrances, or preservatives, trigger inflammation that makes the skin more reactive even in the absence of the allergen.
The role of the skin microbiome
The microbiome, altered by antibiotics, unbalanced cosmetics, or dermatological conditions, plays a central role. A balanced microbial flora reduces inflammation and raises the skin’s tolerance threshold: research indicates that reduced bacterial diversity is common in people with sensitive skin.
Nerve endings and sensory hyperactivity
The skin contains a complex network of nerve endings that can become hyperactive in some cases. Studies on small-fiber neuropathy indicate that nerve hyperreactivity may explain symptoms such as burning and itching even in the absence of visible signs. This is why a person may experience genuine discomfort even when their skin appears completely normal on examination.
Age and skin sensitivity
- Infants and children: they have an incomplete lipid barrier and a higher pH, making them particularly sensitive to cleansers and temperature changes.
- Adults: excessive use of cosmetics and environmental exposure are the main factors.
- Over 60s: the physiological reduction in sebum, collagen, and cell renewal increases vulnerability.
How it is assessed
Skin sensitivity is identified primarily based on the symptoms reported. However, objective tools are also available and are used mainly in research:
- Lactic acid sting test: assesses subjective reactivity to a controlled chemical stimulus.
- Corneometry: measures hydration of the stratum corneum.
- TEWL measurement: assesses transepidermal water loss, which is often elevated in sensitive skin.
Sensitive skin is a condition, not a disease. However, when symptoms persist, worsen, or are accompanied by visible lesions, evaluation should be carried out by a dermatologist: a cosmetic product can improve comfort and tolerance, but it cannot treat a medical condition.
In summary
Skin sensitivity is a multifactorial, widespread condition that can affect people of all ages and all skin types. Its causes go far beyond appearance and involve the immune, nervous, and hormonal systems, as well as the external environment. Choosing products free from sensitizing substances and maintaining a simple, consistent routine is the strategy that delivers the most reliable results.
For practical advice, see the quick guide on what to do when your skin becomes red and the guide to the causes of and ways to prevent redness.
