Monday, February 17, 2014

Healthy, pesticide- and herbicide-free soil may be the key to good health: Grow your food in it, work it yourself or buy only from people who do

The Surprising Healing Qualities ... of Dirt

A doctor discovers exposure to healthy farm soil holds keys to healthy bodies.
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Potatoes Photo by Paul Dunn
YES! Photos by Paul Dunn
Recently I’ve been enjoying dirty thoughts.
I spend my days in a sterile 8x10 room practicing family medicine and yet my mind is in the soil. This is because I’m discovering just how much this rich, dark substance influences the day-to-day health of my patients. I’m even beginning to wonder whether Hippocrates was wrong, or at least somewhat misguided, when he proclaimed, “Let food be thy medicine.” Don’t get me wrong—food is important to our health. But it might be the soil where our food is grown, rather than the food itself, that offers us the real medicine.
You would find little to support these assertions within the medical literature. Enter the terms “soil” and “health” into a PubMed database and the top search results portray soil as a risky substance, filled with pathogenic yeast, antibiotic-resistant bacteria, radon, heavy metals, and pesticides. But move past these grim reports, and you will uncover a small, but growing, collection of research that paints soil in a very different light. These studies suggest that soil, or at least some types of soil, can be beneficial to our health.
68 Cover
The scientists investigating this soil-health connection are a varied bunch—botanists, agronomists, ecologists, geneticists, immunologists, microbiologists—and collectively they are giving us new reasons to care about the places where our food is grown.

Lively soil, better food

For example, using DNA sequencing technology, agronomists at Washington State University have recently established that soil teeming with a wide diversity of life (especially bacteria, fungi, and nematodes) is more likely to produce nutrient-dense food. Of course, this makes sense when you understand that it is the cooperation between bacteria, fungi, and plants’ roots (collectively referred to as the rhizosphere) that is responsible for transferring carbon and nutrients from the soil to the plant—and eventually to our plates.
Given this nutrient flow from soil microbes to us, how can we boost and diversify life in the soil? Studies consistently show that ecological farming consistently produces a greater microbial biomass and diversity than conventional farming. Ecological farming (or eco-farming, as my farmer friends call it) includes many systems (biodynamic, regenerative, permaculture, full-cycle, etc.) that share core holistic tenets: protecting topsoil with cover crops and minimal plowing, rotating crops, conserving water, limiting the use of chemicals (synthetic or natural), and recycling all animal and vegetable waste back into the land. Much of this research supports what traditional farmers around the world have long known to be true: the more ecologically we farm, the more nutrients we harvest.

Allergy-fighting microbes

While soil scientists are busy documenting these soil-to-food links, immunologists and allergists in Europe are working above ground to uncover another intriguing soil-health connection, the so-called “farm effect.” Why is it that children raised on ecologically managed farms in Central Europe have much lower rates of allergy and asthma than urban children or those raised on industrialized farms? Once again, almost everything points to microbes—in manure, in unpasteurized milk, in stable dust, on unwashed food and, yes, in the soil. In one study, researchers cultured farm children’s mattresses and found a potpourri of bacteria—most of which are typically found in soil.
How soil microbes and other farm microbes protect against allergic diseases is still a matter of debate, but research is increasingly pointing to a new idea which, for lack of a better term, I will call the “microbiome exchange hypothesis.”
The standard explanation for the “farm effect” is the hygiene hypothesis, which contends that early life (including in utero) exposure to a variety of microbes dampens the allergic response of our adaptive immune system. The problem with this theory is that our immune system is surprisingly simplistic and seems to react similarly whether it is encountering the diverse portfolio of microbes on an ecological farm or the relatively homogeneous collection of microbes typically found in an urban apartment or a conventional farm. But what if our own immune cells are simply a backup mechanism to a more sophisticated first line of defense—our resident microbes?
And what if a healthy and diverse soil microbiome can foster a more diverse and protective human microbiome? In fact, newer research suggests that this is the case and that an ongoing soil-to-gut microbial exchange might offer the real “farm effect.”

Gut-level gene swapping

Of course this is all very new—and for me, as a physician, somewhat disorienting. In medical school I was taught that our internal bacteria belong to a private club and that they have nothing to do with the microbes in our external environment. Pathogens such as salmonella or E. coli might pass through, as happens when we suffer from food poisoning or other infections, but their influence was considered to be transient—albeit occasionally devastating. But now that we can sequence the DNA of an entire microbiome, using a technique called metagenomics, we’re beginning to connect the dots and we’re discovering that genetic swaps can take place between our microbiome and the outside world—particularly the places where our food is grown.
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A group of French microbiologists were among the first to document this game of pass-the-gene when they identified the exact same sequence of DNA in two different Bacteroidetes bacteria species, one living on seaweed and the other in the intestines of Japanese people. They concluded that the marine bacteria had hitchhiked their way into the human gut via sushi and other seaweed dishes and passed their seaweed-digesting DNA on to resident microbes of the human host. The end result of this exchange is that many Japanese—and possibly people from other seaweed-eating cultures—have acquired a greater ability than the rest of us to extract valuable nutrients from their nori.
Justin Sonnenburg, a microbiologist at Stanford who studies how our environment influences our microbiome, told me that the findings from this nori study are, most likely, just the tip of the iceberg. He believes that we’ll continue to discover ways that the microbes in soil and oceans are interacting with our microbiome and playing a huge role in our health.

Rx: dirt

Impressed by the growing evidence that our health depends on healthy soil, my “dirty thoughts” have turned to action. I now tell my patients that food grown in well-treated soil might offer distinct advantages when it comes to scoring the best nutrients and building a healthy immune system. Of course, identifying this food can be tricky since USDA Organic certification, while certainly a helpful guide, does not always lead us to the healthiest farms. Many certified organic farms do qualify as ecological, but some large-scale farms with this certification still till deeply and use approved pesticides—both practices that damage soil and the microbes in it. On the other hand, there are farmers who can’t afford organic certification who are implementing the practices of eco-farming, practices that have been shown to produce a rich soil and a thriving microbial population. Since there is no “healthy soil/healthy microbe” label that can steer us toward these farms, my suggestion is to ask this simple question:
“Does the farmer live on the farm?”
Farmers who live on their land and feed their family from it tend to care for their soil as if it were another family member. Going to farmers markets and joining a CSA (community-supported agriculture) are reliable ways to get this type of produce, and supermarkets are also beginning to support local farmers. Remember, the more we demand it, the more they will carry it.
Carrots photo by Paul Dunn
Photo by Paul Dunn
Of course, another option is to grow our own food. Eating fresh-grown food from healthy soil is not an all-or-nothing proposition, and even a daily handful of herbs from a container garden can have a positive impact on our health. Whether it is homegrown or from a local farm, I do mention to my patients that they should think twice before peeling or scrubbing their farm bounty. After all, who knows what beneficial bacteria might be coming along for the ride? By the way, eating fermented farm-fresh vegetables is a great way to get a mega-dose of soil bacteria.
I also tell patients about other (non-edible) health advantages to connecting with healthy farms. For example, although the data is far from conclusive, spending time on a local farm might offer a relatively safe, low-tech prevention strategy for families predisposed to allergies. “Farm time” looks especially attractive if it obviates the need for allergy shots or rounds of antihistamine. Emerging research says time spent working the soil is a means to build community, improve strength and fitness, slow dementia in seniors, and improve school performance in teens. It would be simplistic to promote a connection to healthy farms as a panacea for all that ails us, but it has become an important part of my medical toolkit.

Caring for our dirt

Finally, I have come to see my patients as an integral part of a farm eco-cycle where the flow of health is bidirectional. In other words, our choices directly influence the farm’s health, which, in turn, impacts our health. For this reason, composting is a way to nourish local farms and ultimately fortify ourselves. I encourage patients to protect the soil like they protect their bodies. While many of us are aware that chemicals used in the soil might be harmful to us, we rarely consider how products that we use on ourselves or in our homes—such as triclosans, VOCs, parabens, PBAs, PVCs, and lye—might affect the health of the soil and its microbes. (By the way, rosemary or basil extracts make excellent antiseptics, vinegar is the best cleaner, shea or cocoa butter are perfect moisturizers, and diluted baking soda is an excellent shampoo.)
Similarly, while I’ve long recognized how antibiotics, steroids, and other bactericidal drugs might cause unintended side effects in my patients, I now understand how these drugs can impact the microbial life underfoot and ultimately our own cells.
Certainly, any chemical that decreases microbial diversity will, in turn, decrease the nutritional value of our food. But there is another concern: microbiologists at Washington University in St. Louis have recently noted that soil bacteria exposed to antibiotics and other chemicals can develop antibiotic resistant genes which, similar to the nori-digesting enzyme, can be transferred to our microbiome, turning otherwise benign resident bacteria into “superbugs.”
Thinking of a healthy body as an extension of a healthy farm, and vice versa, is a paradigm shift for many of us. But when we consider that all of our cells get their building blocks from plants and soil then, suddenly, it all makes sense. In fact, it is not too much of a stretch to say: We are soil.

Daphne Miller portraitDaphne Miller, M.D., wrote this article for How to Eat Like Our Lives Depend on It, the Winter 2014 issue of YES! Magazine. She is a family physician, writer, and associate professor at U.C. San Francisco. Her latest book is Farmacology: What Innovative Family Farming Can Teach Us About Health and Healing (William Morrow, 2013).
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Saturday, February 1, 2014

If stream-side ordinance had been in force when apartment complexes were first proposed to go in the Town Branch Neighborhood, flooding wouldn't be so bad there and a lot more natural space similar to World Peace Wetland Prairie and Pinnacle Prairie would have remained in place. Protecting the watershed and preventing flooding and providing urban wildlife habitat and cleansing the air and water quality all would be better downstream

Drainage Causes Concern In Fayetteville

Posted: February 1, 2014 at 5 a.m.
A 60 foot section of Scull Creek crosses the front of the vacant lot at 517 N Walnut St in Fayetteville. Because the section of creek is on the cites protected streams map it is preventing construction activities within 50 feet of the stream bank.
FAYETTEVILLE — City officials plan to start a million-dollar drainage project this year that’s been on the to-do list for at least a decade.
“If you want to look at and prioritize projects, this is the biggest one,” Chris Brown, city engineer, said Thursday. “It’s just something we haven’t been able to afford until now.”
The project, in the Washington-Willow neighborhood north of Lafayette Street and east of College Avenue, will divert stormwater from an undersized culvert that backs up in heavy rain.
Sections of the culvert are estimated to be at least 70 years old. In some places it’s a 4-foot-tall channel with stone walls on either side and nothing but soil underneath. In other places, it’s choked to a 30-inch-diameter pipe.
At A Glance
Streamside Protection
Fayetteville’s streamside protection ordinance, enacted in March 2011, prohibits a range of activities within 50 feet of waterways listed on the city’s protected streams map. Restricted activities include:
• Grading, dredging, dumping, filling or similar construction activities
• Landfills, junkyards, salvage yards
• Clearing of non-invasive woody vegetation
• Storage of hazardous material or chemicals unless in waterproof containers and in a structure
• Parking lots
• Buildings and accessory structures with a building footprint larger than 150 square feet
• Parking or storage of motor vehicles
• Septic systems and/or lateral lines
• In-ground pools
• Animal feedlots or kennels
• Housing, grazing or other maintenance of livestock
• Cultivation
• Land application of biosolids
The following activities are allowed in the streamside zone:
• Stream bank restoration or stabilization
• Water quality monitoring, education and scientific studies
• Revegetation and reforestation
• Dam maintenance
• Stream crossings, including driveways, roadways, trails or railroads
• Maintenance and upgrades of utility facilities
• Maintenance of drainage capacity in the channel, including tree and sediment removal
• New stormwater conveyances when the city engineer determines there's no practical and feasible alternative.
Source: City of Fayetteville
The drainage system runs under or near several houses on Maple Street and Walnut Avenue, making it difficult for city crews to remove brush and debris.
The culvert became especially clogged during April 2011 flooding. With nowhere else to go, water popped a manhole cover and poured into yards and multiple homeowners’ basements. What looked like a river rushed down Walnut Avenue.
Eden Reif, who lives at 607 N. Walnut Ave., remembered water up to the top step of her basement.
“To say that it was exciting would be an understatement,” Reif said Friday.
Reif, like other neighbors in the area, doesn’t know what to think about the upcoming project.
“We want to know what they’re planning before we just say, ‘Sure, go ahead,’” she said.
The city will have to acquire land from several property owners to make repairs, Brown said. Streets and sidewalks will be torn up, and longstanding trees may have to be uprooted.
According to preliminary designs, the new drainage system will direct water from a culvert on Olive Avenue, underneath Maple Street and Walnut Avenue and into Scull Creek on the south side of Rebecca Street — in Reif’s backyard.
Brown said a construction timeline isn’t set, but work should get under way sometime this year.
Residents are also concerned about a 60-foot section of Scull Creek on the west side of Walnut.
Engineering staff in January recommended removing the section of creek from the city’s protected streams map.
The map identifies streams with a watershed of at least 100 acres in Fayetteville. A range of activities, including grading, dredging and clearing of non-invasive woody vegetation, are prohibited within 50 feet of protected waterways, according to the streamside protection ordinance, which aldermen approved in March 2011.
Removing the section of creek from the protected streams map would allow Clay Morton to build a house close to the street on what for years has been a vacant lot at 517 N. Walnut Ave. Otherwise, the house would have to be set back at least 50 feet from the creek.
Morton said Thursday he’s wanted to build a house in the Washington-Willow neighborhood for years.
“My wife and I have always wanted to live down there,” he said.
Washington County property records show Morton purchased the 0.2-acre tract in November from Thomas and Mary Kennedy for $80,000. He then began clearing trees on what had been a heavily wooded property.
After a complaint from a neighbor who was aware of the streamside ordinance, city engineers sent Morton a letter warning him to stop clearing the land. Brown said the tree cutting continued, however, and another notice had to be issued Jan. 23. Morton was told he would need to reseed areas where the trees were removed. Brown said Morton won’t be allowed to build near the creek as long as it’s included on the protected streams map. Morton could be fined if he doesn’t mitigate damage that’s been done.
Chris Kaiser, who lives next door to Morton’s property, said Friday she’s opposed to any change to the protected streams map.
“I do not believe that sections of the map should be requested to be removed … just because a developer … might be inconvenienced by having to protect the streamside zone, especially when said developer has already denuded the lot he purchased in violation of the streamside ordinance,” Kaiser wrote.
Kaiser said the protected streams map shouldn’t be modified until city engineers have finalized the design for drainage repair and communicated their plan with neighbors.
Morton said he wasn’t aware of the restrictions on his land when he bought the property.
He said he’s designed two scenarios for the house he wants to build: one with the house close to the stream and aligned with his neighbor’s houses and one with the house farther back from the street.
Morton added the city’s drainage repair should ease flooding on Walnut.
“I feel confident from what I’ve seen of the plans that it’s going to resolve the issue,” he said.
City Council members are scheduled to consider removing the 60-foot section of Scull Creek from the protected streams map Feb. 18.
Web Watch
Flooding Video
Go to the online version of this report at to see a video of April 2011 flooding on Walnut Avenue.