Exploring Linkages Between Soil Health and Human Health

Recent scientific advances have facilitated exploration of the microbiome and are spurring interest in how microbial communities are connected among species and how attention to microbiomes can support soil health, food quality, and human health. There is also the possibility that new discoveries in the soil microbiome could facilitate drug development and address threats to human health, including antibiotic resistance, contaminants, and soil-borne pathogens.

Finally, there are questions about whether management practices are linked with the nutrient density of the food produced and about the interactions of the soil microbiome with soil contaminants. Therefore, the U.S. Department of Agriculture’s National Institute of Food and Agriculture asked the National Academies of Sciences, Engineering, and Medicine to convene a committee of experts to explore the linkages between soil health and human health (see Figure 1). The committee approached its task from a One Health concept, which posits that soil should be valued as an ecosystem that, when healthy, contributes to the health of other ecosystems, plants, humans, and other animals.   Here are the highlights of their June 2024 report.​

These notes were prepared by LWV UMRR Board member Mickey Croyle (LWV St Louis, MO), based on a webinar given by the National Academy of Sciences on June 13, 2024.   To obtain a copy of the full report, click here.  

The graphic above was used to show relationship and need to study throughout then presentation
USDA, Food and agriculture funding paid for the report to look at human health, animal health, soil, environmental heath and define the relationship for soil and human health.  The mycobiome needs to be studied in greater detail.  The soil biodiversity in mycelium (fungus) and microorganism is implicit in this aspect. DNA sequencing is getting better understanding. Healthy soil with intact microbiome affects animal and human gut microbiome.
Soil health correlates to people:
- food supply
- nutrient quality
- water requirement and supply
- suppression of disease

LINKAGES BETWEEN SOIL MICROORGANISMS AND HUMAN HEALTH
The most obvious linkage between soil microorganisms and human health rests on the fact that soil microorganisms do the work needed to produce food, including cycling nutrients and carbon, filtering
water, and building soil structure and organic matter. Perhaps less recognized is the critical role the soil microbiome plays in climate regulation, including carbon sequestration, and the ability of soil microbes to metabolize many organic contaminants into harmless byproducts, which limits exposure to humans. 

We need to advance our understanding of linkages between soil microorganism and human health:
- more robust sampling with enhanced data re-utilization that will quantify the microbial roles in human and soil health
- improved decoding and diagnostic platforms to more effectively monitor the heterogeneity and dynamics in microbiomes
- support cross domain collaboration to prove an integration microbiome understanding that spans the soil to human continuum.

LINKAGES BETWEEN AGRICULTURAL MANAGEMENT PRACTICES AND HUMAN HEALTH
Common agricultural management practices have increased crop yield and food security, but this productivity has often come at the expense of soil health, with detrimental effects on the environment
and human health. For example, synthetic fertilizer use has greatly increased crop production but also caused excess nutrients to leach from agricultural fields, sometimes resulting in contaminated groundwater, algal blooms, and production of potent greenhouse gases that contribute to climate change. At its most fundamental level, agricultural management practices often create trade-offs between the many services soils provide to people; for example, food production on the one hand and, on the other, the ability of ecosystems to sustain biodiversity, sequester carbon, and perform myriad other functions that are equally, even if less obviously, essential to human health. 

Nutrient availability in the soil and environmental conditions, management practices and plant genetics all participate in determining nutrient density in the food supply.  Pre-quality and post harvest variables also affect nutritional quality of food consumes. This makes it difficult to identify direct linkages from soil health to crop nutritional quality and effect on human health
- Food composition
-food processing
- foodborne pathogens
mycotoxins
- consumer food choices

LINKAGES BETWEEN AGRICULTURAL MANAGEMENT PRACTICES AND THE NUTRITIVE VALUE OF FOOD
Although there is a common perception that healthy, well-managed soils produce healthier foods, the connection is not always clear. Nutrient availability in the soil, environmental conditions, management practices, and plant genetics all play a part in determining the nutritional quality of food. Comparative studies of different production systems (e.g., conventional versus organic) have tried to assess the interplay of these factors, but variations in experimental design, soil types, crop species, and environmental conditions have yielded divergent results.
What ultimately determines the nutritional quality of food crops is the amount of essential nutrients with health-promoting potential that are transported to, or synthesized within, the edible portion of the plant. These include minerals and biosynthesized macromolecules such as amino acids/proteins, carbohydrates, lipids, vitamins, and phytochemicals. 

We need to advance understanding of linkages between agriculture management practices and the nutritive value of food requires:
- translation research to understand the effect of practices on nutrient and bioactive density of crops
- Research to understand how food composition can be influenced by management or breeding to achieve higher levels of health beneficial compounds
- Research to understand the utility of bio stimulants in nutrient uptake and yield and potential effects on indigenous soil
- Research in food processing technology that enhance profile of health beneficial nutrients and compounds.


IMPROVING SOIL HEALTH TO IMPROVE HUMAN HEALTH
A healthy soil sustains biological processes, decomposes organic matter, and recycles nutrients, water, and energy, reducing the need for synthetic fertilizers and irrigation. It helps mitigate exposure to some chemical contaminants and sustains food production. All of these functions make the prioritization of soil health for human health benefits even more important in the face of climate change, which will adversely affect soil nutrient cycling and exacerbate the detrimental effects of flooding or drought on soil stability and water-holding capacity. 

Improving soil health to improve human health needs:
-better quantification of soil health using a national monitoring approach
- more long term and on the farm research to better understand the underlying mechanism of soil health
- research into management practice that overcome potential trade offs from common agriculture practices
-research that increase the safe and effective use of underutilized resources
- investment in plant breeding fro more complex systems
- Farm program support for practices that impove soil health and increase crop spatial and temporal diversifications.

GOING FORWARD
Shifting the perception of soil to a valued ecosystem that is interconnected with the health of plants, humans, and other animals will be spurred on by a better knowledge of underlying mechanisms contributing to soil health
and its connectedness to plant and human health, and a continued optimization of ways to quantify and compare health. It will require changes in farm-support programs to value soil health as a metric of success and to transition toward more complex and perennial cropping systems as well as increased circularity where waste streams are turned into safe resources. Finally, societal awareness of the role soil health plays in human health beyond food production must increase, which will require the involvement of many federal agencies, scientific societies, companies, and international organizations.

We need to increase awareness of relation health and soil.
Federal agencies and scientific societies should continue their work to promote the public awareness of the importance of soil health and societal value beyond the immediate material benefits:
Interrelationship between the build environment, water habitat  wild animals, humans soil and plants, air, land. 

COMMITTEE ON EXPLORING LINKAGES BETWEEN SOIL HEALTH AND HUMAN HEALTH Diana H. Wall (Chair), Colorado State University; Katrina Abuabara, University of California, San Francisco; University of California, Berkeley; Joseph Awika, Texas A&M University; Samiran Banerjee, North Dakota State University; Nicholas T. Basta, The Ohio State University; Sarah Collier, University of Washington; Maria Carlota Dao, University of New Hampshire; Michael A. Grusak, U.S. Department of Agriculture’s Agricultural Research Service; Kalmia E. Kniel, University of Delaware; Ylva Lekberg, MPG Ranch; University of Montana; Rebecca Nelson, Cornell University; Kate M. Scow, University of California, Davis; Ann Skulas-Ray, University of Arizona; Lindsey Slaughter, Texas Tech University; Kelly Wrighton, Colorado State University
STUDY STAFF Kara N. Laney, Study Director; Roberta A. Schoen, Director, Board on Agriculture and Natural Resources; Ann L. Yaktine, Director, Food and Nutrition Board; Katherine R. Kane, Senior Program Assistant (through March 2024); Samantha Sisanachandeng, Senior Program Assistant (from April 2024)

FOR MORE INFORMATION
This Consensus Study Report Highlights was prepared by the Board on Agriculture and Natural Resources based on the Consensus Study Report Exploring Linkages Between Soil Health and Human Health (2024).
The study was sponsored by the U.S. Department of Agriculture’s National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project. Copies of the Consensus Study Report are available from the National Academies Press (800) 624-6242 | https:// nap.nationalacademies.org
Division on Earth and Life Studies
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