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  • Writer's pictureDoug Toal

Dirt: The Ancient Probiotic

Do we all agree that diversity is a good thing? Of course we do. It’s one of the most important characteristics of successful corporations and societies. When people from diverse backgrounds get together to share views and solve problems, they bring together a wide array of experiences and are better able to cope and adapt to change.

If you’re not convinced, consider the positive impact that diversity has had on multi-cultural nations such as the USA. Did you know that almost half of the nation’s largest corporations were founded by first and second generation immigrants? Immigrants fled structured, homogenous, and class-based societies in order to pursue happiness and prosperity in a new society that awarded innovation and hard work. These people caused disruptions in the status quo and pulled an established populace out of complacency by encouraging competition.

If you’re still not convinced that diversity is a good thing, then I invite you to consider what’s going on in your gut. In the same way that corporations and societies benefit from diverse populations of people and ideas, our bodies benefit from a diverse population of gut microorganisms. Microbial population diversity encourages competition for nutrients and sites of colonization. Diversity prevents single species of microorganisms to gain dominance over other species in order to implement agendas that are unhealthy to the host (i.e., you and me). The evidence is clear, and clinical research has proven, that the lack of gut flora diversity promotes obesity, diabetes and a plethora of other chronic disease.

If you’ve read my past blogs, you’ll know that I am a big proponent of healthy diets and supplement use in order to promote a happy and diverse gut flora population. It’s important to understand that when you eat, you are not only feeding yourself, but you are feeding trillions of microorganisms. With every bite you take, you are either creating an environment that nourishes diversity or you are depriving the beneficial bacteria in your gut. These beneficial bacteria help you digest food, control the calories you absorb and provide vital enzymes and vitamins as well as keep our immune systems healthy.

So, what kinds of food promote diversity? Dietary fibers from fruits, vegetables, whole grains and legumes. Unlike other foods, such as fats, proteins or simple carbohydrates, which your body easily breaks down and absorbs, dietary fiber isn’t digested by your body. Instead, it passes relatively intact through your upper gastrointestinal tract and into your large intestines to become a feast for the beneficial bacteria in your colon. You see, while our bodies are incapable of digesting dietary fiber, the trillions of bacteria that reside within us have been consuming the stuff for eons. What’s more, they break the fiber down into fermentation products that our bodies need and crave for energy, such as short chain fatty acids.

When you skimp on dietary fiber, the beneficial, fiber-loving bacteria in your gut starve and your intestinal flora becomes less diverse. This allows the bad acting, toxic strains to flourish and wreak havoc on your systems through chronic inflammation and oxidative stress. I’m sure you’ve heard the old adage that “when the cat’s away, the mice will play”. Eating over processed food and shying away from healthy fiber is akin to sending the “cat” away since you are diminishing the healthy microbiota inside your gut.

To help in your efforts to promote a diverse and healthy population of gut bacteria, consider some of these foods:

· Garlic, leeks and onions provide a dense source of a hard to digest carbohydrate known as inulin.

· Lentils and other legumes are a rich source of fiber.

· Despite their high fat content, various types of nuts are an excellent source of polyphenols and fiber.

· Extra virgin oil provides a rich source of polyphenols that microorganism use to help produce antioxidants.

· Dark chocolate, with a high cocoa content (70-85%), provides a rich source of polyphenols

· Apples provide an excellent source of nutrients and pectin, a dietary fiber that microorganisms thrive on.

· Cultured dairy (i.e., yogurt, kefir, and unpasteurized cheese) and fermented vegetables contain live probiotics that promote diversity and healthy gut function.

You may have noticed that the above list does not contain processed food like breakfast cereals (low-fat of otherwise), pasteurized cheese, bread, savory snacks (i.e., low fat chips), soft drinks, or microwave and ready-to-eat meals. That’s because these types of foods usually get fully absorbed into our bodies and used for energy or fat storage and they don’t make it into our large intestine to feed our gut bacteria.

You may have also noticed that the above list contains many of the foods that have sustained humans for centuries, such as vegetables, nuts and legumes. It’s hardly coincidental that the very foods that feed and nourish our gut bacteria are the very same foodstuffs that our ancestor ate. In order to derive nutrients from plant life, our ancestors needed a partner to help digest foods that were high in indigestible dietary fiber. Fortunately, gut bacteria work with us to provide that perfect partnership. This is something that scientists refer to as a symbiotic relationship where both the host (i.e., you and me) and our gut flora (i.e., the beneficial microorganisms in our intestines) benefit.

The finely-tuned symbiotic relationship that humans have developed with gut microorganisms over centuries of co-dependence has been skewed recently as technological advancements have allowed mass production of food products that lack the nutrients that our gut flora crave. Compared to our recent ancestors, who lived outside of cities and ate rich and varied diets without antibiotics, we now have only a fraction of microbial species living in out intestines. Is it any wonder that obesity and chronic disease such as type 2 diabetes has reach the status of a worldwide epidemic?

This brings me to the topic of good old fashioned dirt. I am often impressed by the rows upon rows of glistening, thoroughly scrubbed fruits and vegetables that are on display in our local grocery stores. Once we buy the produce, we are advised by the FDA to wash them further before consumption in order to eliminate any trace of chemicals and pathogens. Since most of us do not have the luxury (or patience) of growing fruits and vegetables in our own organic garden, we cannot be certain that they are thoroughly free of harmful pesticides or contaminating pathogens and so the FDA’s advice is sound and worth paying notice to.

However, long before the mass use of pesticides and well before pathogens from livestock runoffs contaminated our fruits and vegetables, our ancestors were frequently exposed to a healthy dose of soil with each vegetable serving. It’s likely that that our ancestors ate their fruits and vegetables when and where they could and it’s certain that the FDA wasn’t around to advise them to give each serving a good wash and scrub. The result of all this was that they consumed the bacteria that existed naturally within the soil. In case you’re wondering, a handful of garden soil holds more microbes than the number of stars in the known universe and a quick online search reveals that the observable universe contains 1 billion trillion stars! Even a pinch of soil contains enough bacteria to put many commercial probiotic supplements to shame.

Our ancestors, with their varied diet of fruits and vegetables, and their constant ingestion of soil-based bacterial species, cultivated a diverse and healthy population of gut microorganisms. Nowadays we live in sanitized environments and we consume foods that are sterilized and lacking in nutritious fiber. But the generations of humans before us lived closer to the earth, and indeed consumed portions of it. That’s why good, old-fashioned and healthy soil was the first probiotic known to mankind.

I think we can learn a thing or two about proper dieting from our ancestors. Perhaps they didn’t know it at the time but they were experts at cultivating diversity within their gut flora. With a healthy dose of dietary fiber and exposure to soil-based probiotics through healthy supplementation, we too can experience health and happiness.

About the author:

Douglas Toal, PhD is a Clinical Scientist with extensive knowledge and expertise in medical laboratory sciences, metabolism and anti-aging medicine.

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