Seasonal Shifts in the Skin Microbiome: Exploring Dynamic Changes Across the Year

The skin microbiome is a dynamic ecosystem shaped by both internal and external factors. Ongoing research aims to distinguish natural fluctuations from those driven by environmental influences.

What We Know:

• Facial skin is particularly sensitive to environmental factors like temperature, humidity and UV exposure, leading to variations in microbiome composition across different climates. For instance, UV radiation increases sebum production, promoting the growth of lipophilic microorganisms such as Cutibacterium acnes and Malassezia, while warm temperatures (33.2–35.0°C) further support their growth by boosting sebum secretion. Higher humidity levels tend to enhance bacterial diversity (Tao et al., 2024).

• One study highlighted this variability, showing that individuals in northwest China’s dry, high-altitude regions had lower Malassezia and bacterial diversity but higher ceramide and fatty acid levels compared to those living in the warm, humid southern regions (Tao et al., 2024).

Industry Impact and Potential:

• A study tracking microbiome variability over the course of a year found that Cutibacterium was more abundant in winter, correlating with increased transepidermal water loss (TEWL), a measure of skin barrier integrity. In contrast, Corynebacterium, Staphylococcus and Streptococcus were more abundant in summer. These changes in bacterial populations were linked to fluctuations in skin hydration, elasticity and TEWL (Seo et al., 2023).

• Interestingly, hydration levels did not show significant seasonal variation, but elasticity was higher in summer, aligning with the increased abundance of Staphylococcus and Streptococcus. The study also revealed that TEWL was significantly higher in winter, while Cutibacterium abundance and TEWL decreased from winter to summer (Seo et al., 2023).

• These findings highlight the importance of adapting skincare routines to seasonal changes to maintain microbiome health and barrier integrity. In colder months, increased TEWL from low humidity can be countered with hydrating products containing humectants like hyaluronic acid and barrier-strengthening ingredients like ceramides (Proksch, 2008).

• In warmer, humid conditions, lightweight, non-comedogenic products and consistent sunscreen use can manage oil levels while protecting against UV-induced microbiome shifts and barrier damage (Seo et al., 2023).

Our Solution:

At Sequential, we lead the way in microbiome research with a robust database of over 20,000 microbiome samples, 4,000 ingredients and a global network of 10,000 testing participants. Our solutions offer customisable microbiome studies and product formulations, with a focus on preserving microbiome integrity. Whether exploring the skin, scalp, oral or vulvar microbiome, Sequential is your ideal partner in advancing microbiome research.

References:

Proksch, E. (2008) Protection Against Dryness of Facial Skin: A Rational Approach. Skin Pharmacology and Physiology. 22 (1), 3–7. doi:10.1159/000159771.

Seo, J.Y., You, S.W., Gu, K.-N., Kim, H., Shin, J.-G., Leem, S., Hwang, B.K., Kim, Y. & Kang, N.G. (2023) Longitudinal study of the interplay between the skin barrier and facial microbiome over 1 year. Frontiers in Microbiology. 14, 1298632. doi:10.3389/fmicb.2023.1298632.

Tao, R., Li, T., Wang, Y., Wang, R., Li, R., Bianchi, P., Duplan, H., Zhang, Y., Li, H. & Wang, R. (2024) The facial microbiome and metabolome across different geographic regions. Microbiology Spectrum. 12 (1), e03248-23. doi:10.1128/spectrum.03248-23.