WARNING!
This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.
By Dr. Mercola
The bacteria in your body, once thought to be more of a nuisance than an asset, are integral to your very survival. Your body is in fact a complex ecosystem made up of more than 100 trillion microbes that must be properly balanced and cared for if you are to be healthy.
This system of bacteria, fungi, viruses, and protozoa living on your skin and in your mouth, nose, throat, lungs, gut, and urogenital tract, is unique to you. It varies from person to person based on factors such as diet, lifestyle, health history, geographic location, and even ancestry – and it’s vulnerable to your daily lifestyle decisions.
Junk Foods and Unhealthy Meat Allow ‘Bad’ Bacteria to Thrive
While today 80 percent of processed foods are made up of genetically modified (GM) corn and soy, wheat, and meat, 15,000 years ago people ate about 150 different ingredients each week, according to Tim Spector, professor of genetic epidemiology at King’s College London and author of The Diet Myth.1
Spector wanted to find out what happens to your gut if you eat only fast food, specifically McDonald’s, for 10 solid days. His son, Tom, became the willing guinea pig and reported his symptoms, as well as sent stool samples to different labs, throughout the 10-day trial.
“Tom said that for three days he felt ok, but then started to become more lethargic and turned a slight gray color according to his friends. He reported feeling bad the last few days and says he also experienced some withdrawal symptoms,” TIME reported.2
After 10 days of fast food about 40 percent of his bacteria species were lost, which amounted to about 1,400 different types. Losses of microbial diversity such as this have been linked to diabetes and obesity.3
As you continue to subsist on junk food, your gut microbes respond and “bad” bacteria may proliferate, furthering your cravings for more unhealthy foods. As Spector told Food Navigator:4
“Each species of microbe has a preference for certain food sources, which allows them to feed and reproduce. They therefore have their own evolutionary drive to maintain their ecological niche and will do anything to ensure their survival. This includes sending signals to the hosting human that they want more of the same junk food that they thrive on.”
Swapping Your Diet Quickly Alters Your Microflora – For Good or For Bad
A separate study swapped the typical Western diet of a group of African-Americans with that of rural Africans (which meant swapping processed, low-fiber foods with beans and vegetables). In just two weeks, the groups took on the other’s biomarkers of cancer risk such as bacterial activity, fiber fermentation, and intestinal inflammation.5,6
In another study, the hunter-gatherer Yanomami tribe—which had never come in contact with outsiders prior to the researchers’ arrival and had never been exposed to antibiotics—had about 50 percent greater microbial diversity than American subjects.
They also had 30 percent to 40 percent more diversity than the Guahibo and the Malawian tribes, the latter two of which have adopted some Western lifestyle components, such as living indoors and using antibiotics.7 According to one of the authors:8
“As cultures around the world become more ‘Western,’ they lose bacteria species in their guts… At the same time, they start having higher incidences of chronic illnesses connected to the immune system, such as allergies, Crohn’s disease, autoimmune disorders, and multiple sclerosis.
When you eat too many grains, sugars, and processed foods, these foods serve as “fertilizer” for pathogenic microorganisms and yeast, causing them to rapidly multiply. The best way to support microbial diversity is to instead eat a varied diet, including plenty of fiber-rich vegetables and fermented foods while avoiding antibiotics.
In the not-too-distant future, however, it may not be unusual to have your individual gut microbes tested and consume a personalized probiotic product, with four or five different strains tailored to your unique microbial needs, as a result.
Processed Foods Interfere with the Microbes in Your Gastrointestinal Tract
Aside from the sugar and lack of diversity in ingredients, emulsifiers found in processed foods also have a detrimental effect on your microbiome. As reported by Time:9
“Ingredients such as polysorbate 80, carrageenan, polyglycerols, and xanthan and other ‘gums,’ all of which keep ingredients—often oils and fats—from separating.
They are also used to improve the texture and shelf-life of many foods found on supermarket shelves, from ice cream and baked goods, to salad dressings, veggie burgers, non-dairy milks, and hamburger patties.
Now, a new study... suggests these ingredients may also be contributing to the rising incidence of obesity, metabolic syndrome, and inflammatory bowel disease by interfering with microbes in the gastrointestinal tract.”10
In this study, widely used food additives caused chronic colitis in mice with already abnormal immune systems. In mice with healthy immune function, they resulted in mild intestinal inflammation and subsequent metabolic dysfunction that led to obesity, hyperglycemia, and insulin resistance.
Most notably, the emulsifiers were fed at levels that an average person would be exposed to if eating a lot of processed foods, suggesting these additives may indeed affect the health of many Americans.
In addition, the majority of processed foods contain GM ingredients, which are heavily sprayed with Monsanto’s Roundup. The active ingredient in Roundup, glyphosate, is toxic in its own right and causes extreme disruption of microbes’ function and lifecycle.
What’s worse, glyphosate preferentially affects beneficial bacteria, allowing pathogens to overgrow and take over, including the highly toxic Clostridium botulinum. So whenever you eat processed foods, you’re subjecting your microbiome to a number of assaults…
CAFO Meats Harbor Low Doses of Antibiotics and, Often, Antibiotic-Resistant Disease
Animals raised in CAFOs (concentrated animal feeding operations) are routinely given low doses of antibiotics to promote growth and prevent diseases resulting from the crowded and unsanitary conditions of these facilities. Eighty percent of all antibiotics sold in the US are fed to livestock, so eating CAFO-raised foods is likely to be the greatest source of antibiotics for many people.
Not only may this low-dose ingestion of antibiotics have an adverse effect on the composition of your microbiome, thereby affecting your health, but also about half of all meats sold in American grocery stores have also been found to harbor drug-resistant bacteria that can cause severe food-borne illness.
Remember, pathogenic bacteria thrive in unhealthy tissues – whether that be in a plant, animal, or human. It’s nature’s way of taking out the weak and, ultimately, promotes balance in ecosystems. Of course, you don’t want to be one of the weak, which is why caring for the health of your microbiome is so important.
This is one of the reasons why I recommend eating only organically raised, grass-fed or pastured meats and other animal products, such as dairy and eggs, as organic standards do not permit non-medical use of antibiotics.
Bacteria ‘Signaling’ May Detect Disease
Bacteria in your body might one day be used as a method to detect diseases like cancer and diabetes. Research published in the journal Science Translational Medicine found bacteria could be modified to change color in the presence of sugar, which could reveal diabetes (as people with diabetes may have sugar in their urine).11
Additional tests showed bacteria could be altered to change color in the presence of liver tumors, changing the color of urine, or even causing it to give off light, as a result.
The study shows a complex signaling system is at work between your microbes and your body… and your microbes may be able to detect disease before you do. More research is needed before this approach can be harnessed in people, but one day it could lead to in-home testing kits for a variety of diseases, courtesy of your microbial “sensors.”
How Healthy Is Your Microbiome?
All of this information should really drive home the point that optimizing your gut flora is of critical importance for disease prevention and optimal health. Reseeding your gut with beneficial bacteria is essential for maintaining proper balance here. In light of this, here are my recommendations for optimizing your microbial self:
- Fermented foods are one of the best routes to optimal microbial health, as long as you eat the traditionally made, unpasteurized versions. Healthy choices include lassi (an Indian yoghurt drink, traditionally enjoyed before dinner), fermented grass-fed organic milk such as kefir, various pickled fermentations of cabbage, turnips, eggplant, cucumbers, onions, squash, and carrots, and natto (fermented soy).
Some of the beneficial bacteria found in fermented foods are also excellent chelators of heavy metals and pesticides, which will also have a beneficial health effect by reducing your toxic load.
Fermented vegetables are an excellent way to supply beneficial bacteria back into your gut. Most high-quality probiotic supplements will only supply you with a fraction of the beneficial bacteria found in homemade fermented veggies, so it's your most economical route to optimal gut health as well.
- Probiotic supplement. Although I'm not a major proponent of taking many supplements (as I believe the majority of your nutrients should come from food), probiotics are an exception, especially if you don't eat fermented foods on a regular basis or if you’re taking antibiotics.
In addition to knowing what to add to your diet and lifestyle, it's equally important to know what to avoid, and this includes:
| Antibiotics, unless absolutely necessary (and when you do, make sure to reseed your gut with fermented foods and/or a probiotic supplement) | Conventionally-raised meats and other animal products, as CAFO animals are routinely fed low-dose antibiotics, plus genetically modified grains, which have been implicated in the destruction of gut flora | Processed foods (as the excessive sugars, along with otherwise "dead" nutrients, feed pathogenic bacteria) |
| Chlorinated and/or fluoridated water | Antibacterial soap | Agricultural chemicals, glyphosate (Roundup) in particular |