“I think there is a revolution about to happen based on the understanding of the complexity of the soil,” Bramble Partners’ founder Henry Dimbleby mused recently.
New research is revealing several surprising ways in which soil and human health are linked. A reduction in soil contact has been associated with a decrease in gut microbiome diversity. Soil microbes may impact our mood by regulating immune systems and supporting a healthy gut-brain axis. Exposure to diverse soil-borne microorganisms contributes to immune system regulation and may help protect against allergies. This kind of knowledge is set to “completely transform what we see as the value of food”, Dimbleby believes.
Without a doubt these insights are spurring innovation in the agtech sector. IoT-enabled drones, soil sensors and satellite imagery enable farmers to monitor and manage soil health with unprecedented accuracy. Techniques for soil carbon sequestration hope to combat climate change and improve soil structure and fertility. Advanced soil analytics are tracking various components of soil health, including carbon levels and microbial diversity.
These innovations are supported by government initiatives and research funding. The UN-supported One Health concept, for example, emphasises there is no human health without soil, animal and environmental health.
Regen ag and health
Healthy soil with a thriving microbiome helps plants access more nutrients, which in turn could present “a richer nutritional quality for those who eat them,” explains Nina Vinot, business development director at Cybèle Agrocare, a French industrial agri-biotech company that selects and produces microorganisms for agriculture.
She cites a host of new evidence of a significant link between soil health and human health. Experiments have revealed that regeneratively farmed vegetables, for example, present greater levels of antioxidants and polyphenols including carotenoids and flavonoids. One showed a 35%-56% increase in boron, manganese and zinc contents and 18-20% more copper, iron and magnesium.
“This matters because these nutrients present disease-preventing properties from non-communicable diseases like cancer,” she says. All the while, the two leading causes of death globally are cardiovascular disease and cancer which are both linked to the quality of the diet. It matters too for crop resilience. Healthy soils, characterised by abundant organic matter and soil life “react better to droughts and floods, that have become increasingly frequent in a +1.5 °C world,” Vinot points out.
Soil health and gut health
The link between healthy soils and human health is strongly connected to gut health. Studies reveal that soil is by far the most extensive natural microbial gene reservoir on Earth. It’s a key primary source of a healthy intestinal microbiota of humans, with a diversity in number of different species 10 times higher than in the gut. “The soil and gut are superorganisms that can replenish each other,” adds Vinot.
Another study conducted with baboons revealed that the soil is the most dominant predictor of the gut microbiota in this species. That’s 15 times stronger than host genetics, she proclaims. Other studies, like the American Gut Project, show us that gut microbiome diversity increases with the consumption of more different types of plants. Microbiomes, Nina reveals, should be seen as “dynamic fluxes rather than states”.
Glyphosate and the gut
Then there’s the hugely controversial issue of glyphosate. Controversial because of the health risks – the World Health Organization’s cancer agency concluded in 2015 that the herbicide is probably carcinogenic to humans – and sadly a lack of alternatives.
Interestingly, some evidence (though much of it conducted on animal models) suggests glyphosate may pose health risks due to its effects on gut microbes. Vinot points out that the safety studies conducted so far have not yet examined the impact of this chemical on the gut microbiome.
What now?
As our understanding of soil health grows, so do the questions concerning how the new solutions we see in agriculture aiming to improve soil quality bring real impact. How can we standardise measurement and verification of soil health, for example? How can businesses incorporate farmer insights into R&D to better address growers’ needs, whilst safeguarding data concerns?
Some believe that food prices are simply too cheap and that farmers need more financial support and incentives to be able to invest in methods to improve soil quality. According to Vinot, the question is about the structure of the market, whereby producers need to get more of the value of food compared to the share of the price currently captured by distributors and retailers.
She agrees that food prices are a high stake to create a sustainable and healthy food system. It’s estimated that in many Western countries, for instance, the cost of food weighs around 7% of household expenditures. That’s about half what we pay for health.
An increasing focus on the soil microbiome
Amid these calls for changes in the rules of the economic game, the pace of innovation continues at a pip. Microbial biostimulants, biofertilisers and biocontrol agents can restore symbiosis and bring specific functions to plants, for example.
These are “fantastic tools”, agrees Vinot, which can help shift the view that plant health is mostly “curative” as in the pharmaceutical human health world, towards more preventive action – similar to how probiotics have supported human health for decades.
“Now that there is increasing focus on the soil microbiome, we are starting to understand the many ecological services that microbes render to the soil as the basis of the soil food web,” she explains. This includes “feeding a number of critters that are crucial to keep the soil aerated, serving as an extension to plant roots and supporting better access to water and nutrients as binders of soil aggregates which help reduce topsoil loss as a key lever to soil carbon sequestration potential.”
But she reiterates that solutions can’t reach scale if they come at an extra cost to the farmers. She wants to see farmers remunerated “not only for the crops they produce but also for the carbon sequestration and ecosystemic services provided such as the support of biodiversity”. In this context, microbial solutions will be “all the more popular”, she reckons.
High stakes
Another company developing soil health solutions is Norway’s Desert Control. Its primary innovation is a patented Liquid Natural Clay (LNC) technology that restores and enhances soil ecosystems. “Today we may know more about the stars and the universe than we know about the amazing life that goes on in our soils,” Desert Control’s CEO Ole Kristian Sivertsen recently told an event. “I think that by helping those lifeforms down there we may be saving the future of humanity.”