The skin is colonized by a diverse microbiota that plays essential roles in maintaining skin homeostasis, protecting against invading pathogens, and coordinating the innate and adaptive arms of the cutaneous immune system. Microbiota colonization begins at birth and is influenced by various intrinsic and extrinsic factors, including hygiene routine, cosmetic use, antibiotics, geographical location, climate, and seasonality.
Factors Influencing the Skin Microbiome
The skin microbiome is shaped by a complex interplay of intrinsic and extrinsic factors. Intrinsic factors include age, sex, and genetics, which can influence the composition and diversity of the skin microbiome. Extrinsic factors, such as hygiene practices, use of cosmetics, exposure to antibiotics, geographic location, climate, and seasonality, also play a significant role in shaping the skin microbiome.
Hygiene and Cosmetic Use
Hygiene practices, such as the use of soap, cleansers, and other personal care products, can impact the skin microbiome by altering the pH, moisture, and nutrient availability on the skin surface. The use of certain cosmetics and skincare products, including fragrances, preservatives, and active ingredients, can also influence the composition of the skin microbiome.
Antibiotic Exposure
Antibiotic use, whether systemic or topical, can disrupt the delicate balance of the skin microbiome, leading to a decrease in microbial diversity and the overgrowth of opportunistic pathogens. This disruption can have long-lasting effects on the skin microbiome and may contribute to the development of skin disorders.
Geographic Location and Climate
Geographic location and climate can also shape the skin microbiome. Differences in temperature, humidity, UV exposure, and exposure to diverse environmental microbes can lead to variations in the composition and diversity of the skin microbiome across different regions and climates.
Seasonality
The skin microbiome can also exhibit seasonal fluctuations, with changes in the relative abundance of certain microbial taxa corresponding to shifts in temperature, humidity, and other environmental factors throughout the year.