Contact with Soil and Plants Boosts Skin Microbes and Immune Health

Spending time in nature and physically interacting with soil, plants, and natural surfaces can provide measurable health benefits. Recent research indicates that touching natural materials increases the diversity and abundance of microbes on the skin, which plays a key role in supporting the immune system. Mira Grönroos, an ecologist and nature-health researcher, conducted experiments where participants rubbed their hands on soil, peat, and moss for 20 seconds. This brief contact significantly increased microbial diversity on their skin, even after washing. While the idea of more bacteria may seem concerning, a rich microbial community helps maintain balance by preventing harmful bacteria from dominating. Children at a Finnish daycare center spend hours daily playing outdoors in a forest-like environment, often getting covered in mud. Studies tracking these children over several years found that those exposed to natural soil and plants had greater microbial diversity on their skin and fewer potential pathogens compared to children playing in paved yards. This microbial diversity is important for skin health and immune regulation. Further research showed that children playing in microbially enriched environments exhibited changes in immune markers that suggest improved immunoregulation, reducing the likelihood of overactive immune responses. This supports the biodiversity hypothesis, which links environmental microbial diversity with human microbiome health and immune function. Similar benefits have been observed in adults. For example, indoor gardening with microbially rich soil increased skin microbial diversity and anti-inflammatory markers in the blood. Additionally, installing living plant walls in office spaces led to increased skin microbial diversity and decreased pro-inflammatory markers. These findings highlight the potential health advantages of integrating natural elements into daily environments, including urban settings. Encouraging incidental contact with nature—such as touching trees or sitting on grass—could contribute to better skin and immune health without significant risks. While more research is needed to fully understand the impact on specific immune-related conditions, current evidence suggests that regular interaction with natural microbial communities supports a balanced immune system. This underscores the value of embracing outdoor activities and nature exposure as part of a healthy lifestyle.