What Is the Dirt Cure?

healthy soil

Story at-a-glance -

  • Your health and that of your children is directly related to the quality of the food you eat; the quality of the food, in turn, is dependent on the health of the soil in which it is grown
  • Vermont has introduced a bill for a state-level certification program that would allow farmers to have their land and farming methods certified as regenerative
  • The use of cover crops and other forms of soil-restorative, regenerative farming are catching on in the U.S.

By Dr. Mercola

Dr. Maya Shetreat-Klein, a pediatric neurologist in New York and an instructor at New York Medical College, had a frightening experience that is becoming all too common among parents today. After her son turned 1 year old, he began experiencing wheezing, rashes and signs of delayed cognitive development.

After visiting multiple doctors she found an allergist who uncovered her son's severe allergy to soy. Returning her son to health meant removing soy foods from their diet, so she eliminated processed foods and set out to reconnect with nature.1

The journey led her to write the book "The Dirt Cure: Growing Healthy Kids With Food Straight from Soil." In it, she explores the intricate links between food and children's health as well as why so many children are facing allergies.

Her research brought her back to healthy soil, and the dirt cure involves three strategies she believes may improve the health of today's kids (and their parents):

  1. Eating nutrient-dense food from healthy soil
  2. Being exposed to certain microbes
  3. Spending time outdoors in nature

The Healthiest Food Comes From Healthy Soil

There's no question your health and that of your children is directly related to the quality of the food you eat. The quality of the food, in turn, is dependent on the health of the soil in which it is grown. Shetreat-Klein told The New York Times:2 

"The organisms in soil have an impact on the health of our food. Part of what makes fruits and vegetables good for us is the phytonutrients in them — the things that make cranberries red or coffee bitter.

Phytonutrients are part of the plant's immune systems. Organisms in the soil that we might think of as pests actually stimulate plants to make more phytonutrients."

Many American diets are based on foods grown in mineral-depleted, unhealthy soils. This is certainly the case with genetically engineered (GE) processed foods and meat and dairy products from concentrated animal feeding operations (CAFOs).

One of the more insidious aspects of the industrial food system is that, as soil becomes sicker and less able to perform its functions, farmers become increasingly dependent on the chemical technology industry — they become trapped.

The use of glyphosate (the active ingredient in Roundup herbicide) begins a downward spiral, making it necessary for farmers to use more and more herbicides, pesticides, and synthetic fertilizers that kill soil microbes — especially if they're using GE seeds.

Weeds and pests become resistant to glyphosate, so farmers must use more weed and insect killers. Crops become nutrient-deprived, so they're forced to increase their use of synthetic fertilizers.

Weeds and bugs become superweeds and superbugs, and all the while the food becomes less and less nutritious. It's a vicious cycle.

In her quest for healthier food, Shetreat-Klein began growing her own, frequenting farmer's markets and even raising her own chickens, an impressive feat considering she lives in the Bronx, New York, but one she said wasn't as difficult as she'd thought it would be.

Kids Need to Play in (Healthy) Soil

The food many U.S. children eat is seriously lacking in nutrition and is ultra pasteurized, which means any beneficial microbes are killed off in processing.

This is a shame, as it's known that children who consume natural foods in their natural state — like raw milk — have a lower risk of respiratory infections, asthma and allergies. These beneficial microbes aren't only stripped from their food but also from their very environments.

Where children once spent long hours outdoors, they now spend long hours inside sitting in front of screens (often on floors scrubbed clean with anti-bacterial detergents).

The rising rates of asthma, allergies and other autoimmune conditions among children may be the culmination of a dirt-free childhood. The fact is, we're all microbial beings and our children need exposure to microorganisms for reasons we are just beginning to understand.

As Shetreat-Klein explained, it's not only a matter of exposure to microbes but exposure to a diverse variety of microbes that may be most important of all. She told The New York Times:3   

"We used to think that children who grew up on farms were healthier than children in urban environments because they were exposed to more microbes. But studies have found that the number of bacteria in urban environments and on farms is similar.

The difference is the diversity of the bacteria. Microbial diversity seems to have a very powerful impact. Children's immune systems are very social: They like to meet and greet a lot of things.

It seems the more they meet and greet, the more likely they are to be in balance, and the less likely they are to let any one microorganism grow out of control, as occurs with infection."

Indeed, European researchers have discovered that children raised on organic farms have far lower incidence of allergy and asthma compared to those raised on conventional, industrialized farms or in the suburbs. They refer to this as "the farm effect."

According to Dr. Daphne Miller, author of "Farmacology: What Innovative Family Farming Can Teach Us About Health and Healing," "In one study, researchers cultured farm children's mattresses and found a potpourri of bacteria — most of which are typically found in soil."4

Spending Time Outdoors Is a Natural Part of the Cycle

You needn't live on a farm to reap the benefits of healthy soil. Parks, nature preserves and backyards can all provide children and adults with much-needed access to green space and soil microbes. According to Shetreat-Klein:5   

"In one teaspoon of soil there are more organisms than there are humans on our planet. Soil houses about 25 percent of the world's biodiversity.

What we also know from studies is that when children spend time in green environments in natural playgrounds, for example, or in parks and forests they perform better on standardized tests, they're more creative, they're happier and their cortisol levels are lower, so they're calmer and less stressed.

And I think that might be somewhat related to the kind of organisms they're exposed to when they're playing outdoors."

For instance, Mycobacterium vaccaeis a type of bacteria commonly found in soil. Remarkably, this microbe has been found to "mirror the effect on neurons that drugs like Prozac provide."6 It helps to stimulate serotonin production, helping to make you feel happier and more relaxed.

In one animal study, mice that ingested Mycobacterium vaccae had a demonstrated reduction in anxiety and improved learning. The researchers noted that natural exposure to microbes by spending time outdoors may be important for emotional health and behavior: 7

Further, in a study of 2,600 children between the ages of 7 and 10, those with greater exposure to green spaces, particularly while at school, had improved working memory and decreased inattentiveness.8

In that case, a large part of the benefit (anywhere from 20 percent to 65 percent) was attributed to a reduction in exposure to air pollution as a result of the green spaces, but there's also past research that suggests "microbial input" from spending time in nature plays a role in brain development.9

Vermont Bill Introduce Certification for Regenerative Farming

Agriculture the way it's typically done today greatly accelerates the soil aging process. Soils that would have remained viable for millions of years in nature are rendered dead and lifeless by monoculture in a few short years.

Tragically, these soils will take hundreds to thousands of years to recover fully in nature — and not until all agricultural assaults are ceased. Chemical farming results in waterlogged soil that's easily compacted by heavy machinery, rendered impermeable and susceptible to erosion.

One-third of the world's arable land has already been lost to soil erosion. Regeneration is possible, but as it stands most U.S. "farms" are only contributing to soil degeneration; they're not interested in changing their methods to support regeneration.

This is why a new bill announced in Vermont — Senate Bill 159 — is so important. The bill would introduce a state-level certification program that would allow farmers to have their land and farming methods certified as regenerative. Something referred to as "carbon farming," regenerative farming methods include planned rotational grazing, which eliminates the need for chemical fertilizers and tilling and instead supports carbon sequestration in the soil.10

Carbon sequestration refers to taking the carbon from the atmosphere and putting it back into the soil, in a stable form of organic matter. Many scientists say that regenerative agricultural practices can turn back the carbon clock, reducing atmospheric CO2 while also boosting soil productivity and increasing its resilience to floods, pests, and drought.

Organic farming is good. A recent study even found organic farming systems are more profitable and environmentally friendly while delivering equally or more nutritious foods that contain less (or no) pesticide residues compared to conventional farming.11

The regenerative certification, however, goes beyond organic certification, as it informs consumers not only what's not in the food (pesticides, synthetic fertilizers, etc.) but also how the food is raised and how its production actually helps improve the land.

If SB 159 is passed, it will result in a visible seal added to foods. In order to be certified regenerative, the farm must meet one of the following criteria over a three-year period and in each successive year:

  • Increase in topsoil
  • Carbon sequestration
  • Increase in soil organic matter

Jesse McDougall, a regenerative farmer in Shaftsbury, Vermont who first wrote the bill, told EcoWatch:12

"Regenerative farming can rebuild the soil, sequester carbon, produce nutrient-dense food and eliminate the need for toxic chemicals … If we want the next generation of farmers to do this work, it is our responsibility to provide them with the tools that make it possible. We wrote this bill to begin building those tools."

The Use of Cover Crops Is Catching On

A key part of soil regeneration involves the use of cover crops to provide, as regenerative farmer Gabe Brown would say, an "armor" over the soil. This armor can virtually eliminate the need for irrigation when done right. Brown grows cover crops on every acre of crop land each year. The cover crops may be grown before a cash crop, along with a cash crop, or after.

But it's the cover crops that provide the carbon that becomes that all-important "armor" on the soil surface. Cover crops also act as insulation, so the soil doesn't get as hot or cold as it would if bare. This allows microbes to thrive longer. Also, the soil biology heats up the soil, which can extend your overall growing season in colder areas, and it helps prevent soil erosion. Brown especially recommends using cover crop "cocktails," or a multispecies combination, noting:

" … [W]hat I'm trying to do in my operation is mimic native range with the diversity of plant life and the diversity of wildlife, insects, etc. Well, that's what we're really doing with the cover crop cocktail, these multispecies mixes. Today, I plant up to 70 different species in a mix. What we're trying to do is mimic the diversity in nature.

Think of it this way. If you plant a monoculture crop, that soil life is only being fed one root exudate. But if I plant a multispecies with 20 different species in it, that soil life is being fed the root exudates from 20 different plants. In other words, I'm accelerating biological time. We're able to regenerate soils much, much faster than scientists used to think were possible."

In 2012, a Census of Agriculture report found just over 10 million acres of farmland (out of 390 million total) were being planted with cover crops, but its use is growing. In an annual survey of farmers taken in 2014, farmers reported planting double the mean acreage in cover crops reported in 2010.13

Cover Crops Make Financial and Environmental Sense

Farmers who adopt the technique have reported better soil texture, less erosion, and increased crop yields. Farmer Doug Anson, who along with his family now plant cover crops on 13,000 of their 20,000 acres of Indiana farmland, told The New York Times:14

"In the part of a field where we had planted cover crops, we were getting 20 to 25 bushels of corn more per acre than in places where no cover crops had been planted … That showed me it made financial sense to do this."

The U.S. government has even set up a small subsidy system to help farmers offset the costs of cover crops and other regenerative practices, but one major hurdle to cover crops becoming mainstream involves absentee land owners.

Many farmers grow crops on land they do not own but rather lease; they therefore have little incentive to want to improve soil quality on land they do not own. Landowners could, however, offer incentives to farmers to use regenerative practices that would, in turn, increase the value of their land.15

How to Embrace Your Own 'Dirt Cure'

It's clear that paying attention to our soils is crucial to our health and future. Fortunately, change is occurring both on large and small scales. The Natural Resources Conservation Service (NRCS), which is part of the U.S. Department of Agriculture (USDA), has become very committed to understanding and teaching about natural soil health and regenerative agriculture

Not only will regenerating our soils lead to improved food production, it also addresses a majority of resource concerns, such as water. When you add carbon back into the soil, either by adding mulch or cover crops, the carbon feeds mycorrhizal fungi that eventually produce glomalin, which may be even better than humic acid at retaining water, so that you limit your irrigation needs and make your garden or fields more resilient during droughts.

Considering data suggesting we may lose all commercial top soil, globally, in the next 60 years if we keep going at the current rate, such changes cannot move fast enough. The NRCS website is an excellent resource for anyone interested in learning more about soil health, including farmers wanting to change their system.

At present, about 10 percent of U.S. farmers have started incorporating practices to address soil health. Only about 2 percent have transitioned to full-on regenerative land management, such as that taught by Gabe Brown, however. On an individual level, you can get involved by growing some of your own food using some of these regenerative principles on a small scale.

Gardening can help boost your mental well-being and may help promote a healthier microbiome to boot, if you allow yourself (and your kids) to get a bit dirty. Once you get started, I think you'll find that little compares to the joy of interacting with nature, watching your garden grow and flourish, knowing that you're going to get nutrient-dense foods that are not only nourishing you and your family but also helpful for the environment.

Shetreat-Klein also shared the following tips with The New York Times to begin your own "dirt cure:"16   

"Take a trip to the forest with your family … Community gardens are also wonderful. So are farmers' markets. They expose children to fresh foods, which taste completely different. And it also exposes them to potentially healthy microbes through the traces of soil that might be left over on the fruits and vegetables when you buy them at a farmers' market."