What is the skin microbiome?
The skin microbiome is the community of microorganisms that colonise the skin. This page summarises research on its role in barrier function, inflammation, and disease, based on registered clinical studies.
The skin microbiome is the collective term for the bacteria, fungi, viruses, and other microorganisms that reside on human skin. It is also referred to as the skin microbiota or cutaneous microbiome. In the research literature, the skin microbiome is studied as a complex ecosystem whose composition and function are shaped by host genetics, environmental exposures, and skin barrier integrity. The evidence block for this page does not provide a sequence, formula, or molecular weight for the skin microbiome as a whole; it is a community-level entity, not a single molecule.
Research on the skin microbiome centres on the interplay between microbial communities and host immune pathways, particularly those involving skin-barrier integrity and inflammatory signalling. The studies cited here examine this interplay in the context of atopic dermatitis, lymphedema, aging skin, and rosacea.
Research Studies
Vernix caseosa retention and atopic dermatitis prevention in newborns
A clinical trial is investigating whether retaining vernix caseosa—the white, creamy substance that covers the skin of newborns at birth—can prevent atopic dermatitis (AD) in infancy [1]. AD, also known as eczema, is a chronic inflammatory skin disease that usually begins in infancy and causes itching, discomfort, and sleep disturbance. It affects up to one in five children worldwide [1]. The study rationale notes that genetic and environmental factors contribute to AD development, especially those related to skin-barrier integrity and the skin microbiome during early life [1]. The trial focuses on primary prevention, meaning preventing AD before it starts [1].
Skin barrier function and inflammation in aging: the BIA study
A randomized, investigator-blinded, self-controlled pilot study is examining the physiologic response to topical moisturizers among older adults with dry skin [3]. The overarching hypothesis is that skin barrier decline is an important source of chronic inflammation, and that skin barrier restoration with moisturizers can reduce serum biomarkers of inflammation [3]. Secondary objectives include determining the extent to which measures of serum inflammation, skin barrier function, and the skin microbiome change in response to moisturizers [3]. The primary objective is to determine the feasibility for a larger trial [3].
Topical ivermectin and the skin microbiome in rosacea
A single-site, 16-week open-label study at the University of California, San Diego, is assessing the role of topical ivermectin 1% cream and its effect on protease and antimicrobial peptide expression and on the skin microbiome in rosacea [4]. The investigators will first measure serine protease activity, cathelicidin, and the skin microbiome of all subjects [4]. All subjects will receive ivermectin topical cream and will be instructed to apply it daily for 12 weeks [4]. Participants will return for monthly visits during which their clinical symptoms of facial redness and number of facial papules will be scored [4].
Biological profile of lymphedema: inflammatory and lymphatic markers
An observational, cross-sectional study aims to characterize the biological profile of primary and secondary lymphedema by investigating five interconnected biological domains: T helper 2 (Th2)-related inflammation, endothelial activation, metabolic dysfunction, lymphatic biology, and tissue fibrosis [2]. While lymphedema is traditionally considered a disorder of impaired lymphatic drainage resulting in the accumulation of interstitial fluid, increasing evidence suggests that its development and progression involve chronic inflammation, endothelial dysfunction, metabolic alterations, abnormal lymphatic signalling, adipose tissue accumulation, and progressive tissue fibrosis [2]. The evidence block does not specify whether the skin microbiome is directly measured in this study.
Comparison of study designs and populations
| Study | Design | Population | Microbiome measure |
|---|---|---|---|
| Vernix caseosa retention [1] | Clinical trial (primary prevention) | Newborns | Not specified in evidence block |
| BIA study [3] | Randomized, investigator-blinded, self-controlled pilot | Older adults with dry skin | Secondary objective |
| Topical ivermectin in rosacea [4] | Open-label, single-site, 16 weeks | Adults with rosacea | Measured at baseline and during treatment |
| Lymphedema biological profile [2] | Observational, cross-sectional | Primary and secondary lymphedema | Not specified in evidence block |
If you are reading this for personal health reasons
The materials and research described on this page are sold for laboratory research use only. We do not provide dosing, medical guidance, or treatment recommendations. Anyone considering a compound or intervention for themselves should speak to a licensed clinician.
Sources
- [1] Retention of Vernix Caseosa in Newborns for Primary Prevention of Atopic Dermatitis — ClinicalTrials.gov
- [2] Biological Profile of Primary and Secondary Lymphedema: Inflammatory, Endothelial, Metabolic, Lymphatic, and Fibrotic Markers — ClinicalTrials.gov
- [3] Skin Barrier Function and Inflammation in Aging: The BIA Study — ClinicalTrials.gov
- [4] Evaluation of the Inhibitory Effects of Topical Ivermectin on Markers of Rosacea Specific Inflammation — ClinicalTrials.gov