Contact with Soil and Nature Boosts Skin Microbes and Immune Health

Spending time in natural environments and physically touching soil, plants, and trees can improve the diversity of microbes living on our skin, according to recent research. This increase in microbial variety is linked to benefits for both skin health and the immune system. Ecologist Mira Grönroos from the Finnish Environment Institute conducted experiments where participants rubbed their hands on soil, peat, and moss for 20 seconds. Despite rinsing with tap water afterward, the microbial diversity on their skin increased significantly. Such diversity helps maintain a balanced skin microbiome, which can inhibit the growth of harmful bacteria. Children at a Finnish daycare center that incorporated forest floor elements into their outdoor play areas showed greater microbial diversity on their skin compared to those playing in paved yards. Over time, this exposure was associated with fewer potential pathogens and changes in immune markers that suggest improved immunoregulation. These findings support the biodiversity hypothesis, which proposes that reduced environmental biodiversity may contribute to rising immune-related conditions. One bacterial group, gammaproteobacteria, increased on children's skin after playing in natural settings and was linked to higher levels of regulatory T cells, important for immune balance. Similar benefits have been observed in adults. Indoor gardening with microbially rich soil and the installation of living plant walls in offices both led to increased skin microbial diversity and favorable changes in immune-related blood markers. Experts suggest that urban planning should facilitate more frequent and incidental contact with nature to promote public health. While more research is needed to clarify the impact on specific immune diseases, current evidence indicates that interacting with natural materials is a low-risk activity with potential health advantages. Encouraging people to engage physically with natural environments, such as touching tree bark or sitting on grass, may help enhance skin and immune health, highlighting the importance of integrating nature into daily life.