Did you know that it’s estimated 20 times more bacteria (called human “microflora” or “microbiota”) live within and on us than total cells found in the human body?
Considering the average adult human body contains about 10 trillion cells, it amounts to a staggering 200 trillion bacteria using us as a host.
In fact, some evolutionists support a theory that portrays a human as microbiota’s own personal robot, assuming bacteria evolved us for use as a host (rather than our evolving as superior beings).
Regardless of one’s evolutionary beliefs, or how exactly microbiota came to exist, these bacteria provide humans with numerous health benefits—all the way from synthesizing essential human vitamins (e.g., vitamin K, folic acid, biotin) to helping us ward off disease.
Critical to these health benefits are gut microbiota (i.e., bacteria in your digestive tract). Different types of bacteria in your digestive tract have been linked to different illnesses and diseases. It even has been shown that obese humans have gut microbiota populations significantly different from those of their leaner counterparts.
What does this have to do with nutrition?
Well, in a nutshell, everything.
What we eat supports the growth of these intestinal critters. Differences in diet can result in significant changes to microbiota’s size and composition. Both “good” and “bad’” bacteria colonize the digestive tract. We need to eat healthily to support the growth of “good” bacteria, so they can overpower “bad” ones. It’s a fierce microscopic battle in the field of your intestines. Estimates are that at least 80 percent “good” bacteria are needed to provide optimal health. Luckily, specific dietary constituents in some common foods turn the “good” guys into deadly bacterial assassins, vanquishing their “bad” rivals.
Two main dietary components, probiotics and prebiotics, support healthy gut microbiota. A diet rich in each is essential for optimal nutrition and health.
Meaning literally “for life,” probiotics are actual live microorganisms (bacteria, yeasts, etc.) in foods, conferring a health benefit when eaten in sufficient amounts to survive the harsh environment of the stomach, and colonize the intestines (adding to gut microbiota!). These bacteria we eat every day—it makes one wonder if vegetarianism actually exists?—are considered saints in the nutritional world. They aid the “good” microbiota in the intestinal war zone.
Probiotics have been implicated in the following health-related benefits:
• Anticancer potential.
• Decreased risk of heart disease (lower cholesterol and blood pressure).
• Improved immunity and decreased risk of various infections.
• Improved digestion and better absorption of essential minerals.
• Decreased whole-body inflammation (which contributes to many common diseases, such as heart disease, diabetes, obesity, etc.).
• Prevention of “bad” microbial growth in the intestines.
• Treatment of irritable bowel syndrome and colitis (inflammation of the colon).
• Increased satiety and body fat breakdown (i.e., weight loss/decreased weight gain).
Common natural food sources include yogurt, kefir, aged cheeses, fermented soy products (miso, tempeh), cultured milk products (acidophilus milk, cultured buttermilk, etc.), and other fermented foods such as sauerkraut. Now, you know why they list names of bacteria on the yogurt carton!
Prebiotics are human-indigestible food components utilized by “good” microbiota for activity and growth (i.e., prebiotics are food for “good” microbiota). Because prebiotics support growth of all “good” gut microbiota, including probiotics, essentially all the health benefits of probiotics also are true of prebiotics (see above). Prebiotics often come in the form of soluble fibers.
Common natural food sources include oats, whole grains, beans and legumes, some vegetables (e.g., asparagus, tomatoes, greens), some fruits (e.g., berries, bananas), some spices (e.g., garlic), chicory root, jicama, honey, and many other high-fiber foods.
Although still a young science, the possibility of significant positive synergistic health benefits from the consumption of probiotics and prebiotics has moved swiftly through the food science world. The near future holds potential for introduction of many new “functional” food products and supplements with either one or both of these nutritional powerhouses present.
Keep your eyes open!