The Microscopic Zoo within Us
August 15, 2012
By Dr. Mercola
Believe it or not, there's a microbial zoo living inside you, literally trillions of microscopic organisms―more than 10,000 different kinds of them―all co-existing with each other and you.
In fact they outnumber you ten to one and ninety percent of the genetic material, (DNA and RNA) in your body is not yours, it belongs to the bacteria that is located mostly in your gut, but some also live on your skin and even in your nose.
Exactly what those different life forms do has been the subject of some exciting research in recent years, and while a few of these organisms can sometimes wreak havoc with your system, the majority of these little "bugs" are good, helping you digest your food, stay protected from infections, and even keeping your immune system properly regulated to fend off autoimmune diseases like asthma, allergies, and diabetes.
The community of microbes living on and in your body is unique to you – like your fingerprints – and is now being regarded as a key contributor to your overall health.
Bacterial Diversity is Crucial for Good Health
Your body's "community" of microorganisms is so crucial to your health that researchers have compared it to "a newly recognized organ," and have even suggested we consider ourselves a type of "meta-organism" -- in acknowledgment of the fact that we cannot be whole and healthy without the participation of a vast array of bacterial species and strains.
In fact, as shown by research published in the journal Nature, the greater the diversity of bacteria in your gut, the better your health is likely to be, especially as you age.1 The study found that not only does gut bacterial diversity tend to decrease the older you are, but elderly people living in a long-term residential facility, as opposed to in their community, also have less variation in gut bacteria than their peers. So the makeup of your gut bacteria is clearly influenced by multiple factors, including your age, where you live, and, the most important part, your diet.
As you might suspect, people with the most diverse diets also had the most diverse gut bacteria, and had less inflammation and frailty than those with less diverse bacterial populations. Lead author Peter O'Toole noted:2
"Our findings indicate that any two given older people, independent of starting health status and genetic makeup, could experience very different rates of health loss upon aging due to dietary choices that impact their gut bacterial ecosystem … You can think of [diet] as another controllable environmental factor that we can act upon to promote healthier aging."
Less Bacterial Diversity Increases Your Allergy Risks
Inflammatory autoimmune diseases including asthma, allergies, multiple sclerosis, type 1 diabetes and ulcerative colitis have been growing at an alarming rate in the developed world, particularly in urban areas. It's been suggested that part of this epidemic could be due to modern man's reduced contact with microbes and parasites that were common among early humans.
Research in Environmental Health Perspectives recently tested this theory out, and indeed found a link between people's environments, the diversity of microbes on their skin and their risk of allergic reactions.3 Children with allergies had a less diverse array of bacteria on their skin, and children who lived in areas with a variety of native flowers in their yard had more diverse microbes and a lower susceptibility to allergies.
The study's lead author noted:
"It is essential to retain contact with natural habitats, especially in the case of young children. Our findings highlight the importance of green space in urban areas, and of opportunities for urban children to spend some time in the countryside."
Bacteria on Your Skin Help Protect You From Infection
Bacteria on your skin are not only linked to reduced allergies, they've also been shown to interact with immune cells on your skin to boost your protection from infections. While it's long been known that the microbes in your gut play an integral role in your immune response, a study in the journal Science found that microbial communities on your skin offer immune protection that is different from that offered by your gut:4
"Protective immunity to a cutaneous pathogen was critically dependent on the skin but not gut microbiota."
There are about 70 known tribes of commensal -- or beneficial -- bacteria that could be living on your body right now. The word commensal comes from the Latin term "com mensa," which means "sharing a table." Interestingly, signals from your gut microorganisms are sent throughout your body and interact with organisms in your skin and gut mucosa. Researchers are now looking into how these interactions can help with skin conditions like dryness, improve collagen, or stabilize the microflora on your skin to help with irritations.
Gut Microbes Even Affect Fetal Growth During Pregnancy
The composition of a woman's gut microbes actually changes during each trimester of pregnancy in ways that support the growth of the fetus. This is largely influenced bv the hormonal shifts that occur during pregnancy.
Interestingly, research shows the microbes actually become less diverse and the number of beneficial bacteria decline while disease-related bacteria increase. Under normal circumstances, such changes could lead to weight gain and inflammation, but in pregnancy, they induce metabolic changes that promote energy storage in fat tissue so the fetus can grow.5 The study's lead author noted:6
"The findings suggest that our bodies have coevolved with the microbiota and may actually be using them as a tool -- to help alter the mother's metabolism to support the growth of the fetus."
The importance of gut flora continues during and after birth, and may have a profound influence on the baby's health and development. An article in Science Daily reported on the featured findings of one related study,7 stating:8
"Each individual's community of gut microbes is unique and profoundly sensitive to environmental conditions, beginning at birth. Indeed, the mode of delivery during the birthing process has been shown to affect an infant's microbial profile. Communities of vaginal microbes change during pregnancy in preparation for birth, delivering beneficial microbes to the newborn.
At the time of delivery, the vagina is dominated by a pair of bacterial species, Lactobacillus and Prevotella. In contrast, infants delivered by caesarean section typically show microbial communities associated with the skin, including Staphylococcus, Corynebacterium, and Propionibacterium. While the full implications of these distinctions are still murky, evidence suggests they may affect an infant's subsequent development and health, particularly in terms of susceptibility to pathogens."
The health implications of this variation in gut bacteria acquired from birth is exactly what Dr. Natasha Campbell-McBride's research sheds light upon. Her research shows there's a profound dynamic interaction between your gut, your brain, and your immune system, starting from birth. She has developed what might be one of the most profoundly important treatment strategies for a wide range of neurological, psychological, and autoimmune disorders—all of which are heavily influenced by gut health.
I believe her Gut and Psychology Syndrome, and Gut and Physiology Syndrome (GAPS) Nutritional program is vitally important for MOST people, as the majority of people have such poor gut health due to poor diet and toxic exposures, but it's particularly crucial for pregnant women and young children.
Download Interview Transcript
Tips for Optimizing and Protecting Your Microbial Communities
Historically, people didn't have the same problems with lacking diversity in their microbial communities and with their gut health as we do today for the simple fact that they got large quantities of beneficial bacteria from their diet in the form of fermented or cultured foods, which were invented long before the advent of refrigeration and other forms of food preservation.
They were also exposed to microbes on a daily basis, primarily through their consumption of raw foods, which contain a great diversity of beneficial flora, and through simply spending time outdoors in contact with healthy soil. They weren't inundated with antibacterial soaps, hand sanitizers and antibiotics, as we are today at every turn.
Maintaining optimal gut flora by eating raw food grown in healthy, organic soil and 'reseeding' your gut with fermented foods and probiotics (this is essential when you're taking an antibiotic), may be one of the most important steps you can take to improve your health. If you aren't eating fermented foods, you most likely need to supplement with a probiotic on a regular basis, especially if you're eating a lot of processed foods. Poor diet in general, especially one high in fructose and sugar, and each course of antibiotics, extols a heavy price, as it tends to wipe out the beneficial bacteria in your gut, giving non-beneficial bacteria and other pathogens free rein to proliferate unchecked.
You can ferment virtually any food, and every traditional culture has traditionally fermented their foods to prevent spoilage. There are also many fermented beverages and yoghurts.
Fermenting your own foods is a fairly straightforward and simple process, and can provide even greater savings. To learn more, please listen to my interview with Caroline Barringer, a Nutritional Therapy Practitioner (NTP) who has been involved with nutrition for about 20 years.
Download Interview Transcript
Quite a large percent of all the foods that people consumed on a daily basis were fermented, and each mouthful provides trillions of beneficial bacteria—far more than you can get from a probiotics supplement. Moreover, food is the perfect delivery system for probiotics, as it provides both a protective and nourishing medium to help these beneficial bacteria through your digestive tract, improving the chances of implantation and lasting positive health effects.
Here's a case in point: It's unusual to find a probiotic supplement containing more than 10 billion colony-forming units. But when my team actually tested fermented vegetables produced by probiotic starter cultures, they had 10 trillion colony-forming units of bacteria. Literally, one serving of vegetables was equal to an entire bottle of a high-potency probiotic! Fermented foods also give you a wider variety of beneficial bacteria, so all in all, it's your most cost-effective alternative.
So I would strongly encourage you to seriously consider adopting fermented foods in your diet.