Habitual gardening and the human gut microbiota

Historically, humans have interacted with soils and their environment. According to the "hygiene hypothesis", environmental exposures are critical for proper immune function development. Urbanization can isolate humans from microorganisms available in green spaces and promote inadequate fiber intake. These manifestations of urbanization are hypothesized to underlie the increased prevalence of many non-communicable diseases, which are associated with gut microbiota compositions that are distinct from healthy Gardening represents an opportunity for interactions with soil bacteria, as well as production of healthy food. Yet, microbial factors that may underpin the health benefits of gardening are under-investigated. The current case-controlled cohort study enrolled gardening families (n=10) and non-gardening (control) families (n=9). Families included two adults and one child (5-18 years) for a total of 56 participants. All participants provided a fecal sample and diet history questionnaires before (April 2018) and at peak (August 2018) of the gardening season. Soil samples were collected from respective gardening plots at these same time points (n=17). Healthy Eating Index (HEI2015) scores and nutrient analysis were performed. Fecal and soil DNA were extracted, the 16S rRNA gene (V4 region) was amplified, and sequence data were processed and analyzed. Peak season gardening families tended to have greater fecal ASV’s, a greater Faith's Phylogenetic Diversity score, greater fiber intake, and higher abundances of fiber fermenting bacteria (Bacteroides ovatus and Eubacterium xylanophilum group spp.) than peak control families. Soil endemic microbes were also shared with gardening participants fecal samples. This study revealed that the fecal microbiota of gardening families differs from non-gardening families, and that there are detectable changes in the fecal microbial community of gardeners and their family members over the course of the gardening season.LimitedAuthor requested closed access (OA after 2yrs) in Vireo ETD syste