Understanding the Microbial Roots of Seborrheic Dermatitis

Seborrheic dermatitis (SD) is a common inflammatory skin condition primarily affecting the scalp, face and chest. It appears as red, flaky, greasy patches or plaques and can cause itching and discomfort. It is a non-contagious condition varying in severity, from mild dandruff to persistent inflamed lesions.

What we know:

• SD is linked to three main factors: increased sebum (oil) production, colonization by Malassezia yeast, and an abnormal immune response. Genetics, skin barrier dysfunction, environmental triggers and stress also contribute to this condition (Adalsteinsson et al, 2020).

• Malassezia species, especially M.restricta and M. globosa, are abundant in SD. These yeasts hydrolyse skin lipids, producing irritating fatty acids that drive inflammation (Tao et al, 2021).

• SD skin shows increased transepidermal water loss, reduced ceramides, and altered lipid composition, increasing irritation and microbial imbalance (Wikramanayake et al, 2019).

• Research highlights SD occurs across all skin types with treatment needs with preferred treatments varying across the population (Polaskey et al, 2024).  

Industry impact and potential

As insights into SD evolve, the industry has a unique chance to create smarter and more inclusive solutions.

• Microbiome-targeted products: Products that help regulate microbial balance, particularly, may help reduce flare-ups while preserving beneficial species.

• Barrier-supportive solutions: Lipids, ceramides, and pH-balanced systems can strengthen and enhance barrier resilience, addressing underlying weakness.

• Inclusive and culturally sensitive solutions: Treatments designed and tested across all skin tones and hair textures can ensure effectiveness across diverse users.

• Simplified treatment routines: Streamlined regimes can help to address consumer frustration with persistent symptoms and complex, time-consuming treatment.

Our solution

At Sequential, we support the development of next-generation seborrheic dermatitis solutions through deep microbiome profiling and multi-omic analysis. With a global database of 50,000+ samples, we help brands understand how Malassezia, bacterial communities, and barrier function interact across different skin and scalp types. We assess whether formulations rebalance the microbiome, strengthen the barrier, and target inflammation-related biomarkers, enabling the creation of microbiome-safe, inclusive, and effective products. Grounded in robust microbiome science, Sequential empowers brands to deliver targeted and culturally sensitive solutions for seborrheic dermatitis.

References:

Adalsteinsson, J. et al. (2020) Experimental Dermatology. https://doi.org/10.1111/exd.14091

Polaskey, M. et al. (2024) JAMA Dermatology. https://doi.org/10.1001/jamadermatol.2024.1987

Tao, R. et al. (2021) Experimental Dermatology. https://doi.org/10.1111/exd.14450

Wikramanayake, T. et al. (2019) Experimental Dermatology. https://doi.org/10.1111/exd.14006