Apple cider vinegar soaks do not alter the skin bacterial microbiome in atopic dermatitis

PLoS One. 2021 Jun 2;16(6):e0252272. doi: 10.1371/journal.pone.0252272. eCollection 2021.


Introduction: Atopic dermatitis is a common skin disease characterized by altered cutaneous immunity in which patients often exhibit lower skin microbiota diversity compared to healthy skin and are prone to colonization by Staphylococcus aureus. Apple cider vinegar has been shown to have antibacterial effects; however, its effects on the skin microbiome have not previously been well-described.

Objectives: We aimed to examine the effects of topical dilute apple cider vinegar soaks on Staphylococcus aureus abundance, skin bacterial microbiome composition, and skin bacterial microbiome diversity in atopic dermatitis participants compared to healthy skin.

Methods: Eleven subjects with atopic dermatitis and 11 healthy controls were enrolled in this randomized, non-blinded, single-institution, split-arm pilot study. Subjects soaked one forearm in dilute apple cider vinegar (0.5% acetic acid) and the other forearm in tap water for 10 minutes daily. Skin bacteria samples were collected from subjects' volar forearms before and after 14 days of treatment. 16S sequencing was used to analyze Staphylococcus aureus abundance and skin bacterial microbiome composition, and alpha diversity of microbiota were determined using Shannon diversity index.

Results: There was no difference in skin bacterial microbiome in atopic dermatitis subjects after 2 weeks of daily water or apple cider vinegar treatments (p = 0.056 and p = 0.22, respectively), or in mean abundance of S. aureus on apple cider vinegar-treated forearms (p = 0.60). At 2 weeks, the skin bacterial microbiomes of healthy control subjects were not significantly different from the skin bacterial microbiome of atopic dermatitis subjects (p = 0.14, 0.21, 0.12, and 0.05).

Conclusions: Our results suggest that daily soaks in 0.5% apple cider vinegar are not an effective method of altering the skin bacterial microbiome in atopic dermatitis. Further studies are needed to explore the effects of different concentrations of apple cider vinegar on skin microflora and disease severity.

Trial number: UVA IRB-HSR #19906.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetic Acid / administration & dosage*
  • Administration, Cutaneous
  • Adult
  • Anti-Bacterial Agents / administration & dosage*
  • Case-Control Studies
  • Dermatitis, Atopic / drug therapy*
  • Dermatitis, Atopic / microbiology
  • Female
  • Humans
  • Male
  • Malus / chemistry*
  • Microbiota / drug effects*
  • Pilot Projects
  • Skin / drug effects*
  • Skin / microbiology
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / growth & development*
  • Young Adult


  • Anti-Bacterial Agents
  • Acetic Acid

Grants and funding

This study was funded by the University of Virginia, UVA Child Health Research Center, the Pendleton Pediatric Infectious Disease Laboratory, and the Department of Dermatology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.