Soil2Gut project by Leiden University
Between July and September 2025, the Leiden University research team joined us around Rotterdam on farmers supplying the Food Pharmacy project to research their soil and plant microbiome and the connection with nutrient density. This is an important milestone in our work connecting farming and healthcare systems.
Leiden University research team with HarvestCare founder, Zuzanna
Researching soil-human health connection
The Soils2Guts project, led by researchers at Leiden University, explores the intricate connections between soil health, agricultural practices, plant microbiomes, and human well-being. With a multidisciplinary approach, the research examines how different farming methods—ranging from conventional to organic and biodynamic—impact soil microbial diversity, nutrient availability, and ultimately, the nutritional quality of food. By analyzing both soil and plant samples, the project aims to uncover how these factors influence human health, particularly through the gut microbiome and immune system. This research contributes to a growing body of evidence supporting the idea that sustainable farming practices not only benefit the environment but also play a crucial role in producing food with higher nutrient density, reinforcing the concept of food as medicine.
Food Pharmacy farmacy farmers participation in the project
Within the project, 9 farmers supplying food for the Food Pharmacy through Rechtstreex were active participants, contributing with their soil and crop samples for scientific analysis. Their involvement was essential in bridging the gap between regenerative farming and nutrition science, helping to generate real-world data on the impact of different farming methods on food quality.
By participating in Soil2Guts, our farmers gain deeper insights into their soil's microbial health and its effects on produce. This data is also crucial for HarvestCare's mission of incentivising the healthcare system to invest in food as medicine solutions. While doing so, it’s necessary to ensure that food used as a medical intervention comes from healthy soil.
Isabel Siles Asaff, Phd candidate, soil science
One of the researchers involved in the project, Isabel, is a PhD candidate at Leiden University, focusing on the relationship between soil health and agricultural practices. Her research explores how farming methods modify microbial biomass in the soil, affecting soil respiration, compaction, and nutrient availability. By analyzing samples from organic, biodynamic, and conventional farms, she aims to map out a gradient of microbial diversity and soil function rather than presenting a black-and-white comparison of farming practices. Her work examines not only the presence of soil microorganisms but also their activity levels, the role of soil compaction due to heavy machinery use, and the availability of essential micronutrients for plants.
Marieke Elfferich, Phd candidate, plant science
Marieke, another PhD researcher in the Soils2Guts project at Leiden University, focuses on the plant microbiome and chemical composition, exploring how different soil conditions and farming practices influence the quality of food. Her research investigates whether agricultural methods impact the microbiome of plants, which in turn may affect human immune systems and overall health. She collects and analyzes plant samples—such as carrots—from various farms, measuring their chemical composition and microbial diversity using DNA sequencing techniques.
Marieke’s work aims to determine whether certain farming methods result in crops with a richer and more beneficial microbiome, potentially enhancing their health benefits when consumed. Her research highlights the crucial link between soil, plant, and human health, reinforcing the idea that nutrient density should be a key factor in evaluating food quality. She hopes that by providing concrete scientific evidence on these connections, her work will contribute to shifting consumer behavior and influence how food is valued in the market, ultimately promoting agricultural practices that prioritize both environmental sustainability and human health.
The preliminary results of the research will be available in Q2 2025. We look forward to report on them further.