Science & medicine have come along way since "germ theory" was finally accepted.
It used to be common practice for doctors to perform surgery, or deliver babies, directly after examining dead, disease-infected bodies; but for hundreds of years, they refused to believe that unseen bugs on their hands were the cause of death for many of their patients.
In fact, up until the late 1800's, advocates for hand-washing were ridiculed, even beaten to death, for offending physicians with such outrageous accusations as to call them "unclean".
Science & medicine sure have come along way.
“Do the best you can until you know better. Then when you know better, do better.” —Maya Angelou.
The intention of this article is to lay out the unbiased, scientific facts (so far as we know it) regarding the micro-organisms we call probiotics - what they are, how they work & how they're manufactured - with hope that you can make an informed decision about if, when & what to supplement.
The Role They Play
Scientists have now determined that 100's of trillions of microorganisms symbiotically co-exist on our skin, in our nose, lungs & digestive tract, and they out number our cells 10:1.
To be clear, the human body consists of roughly 50 trillion cells, so that's 500 trillion microbes covering nearly every surface of your body.
500 trillion... 500,000,000,000,000 (that's a lot of zeros).
The human gut alone, contains 10's of trillions of microorganisms that help us digest food, produce vitamins, balance electrolytes, and most importantly, these "probiotics" play a pivotal role in our immunity to infectious disease.
These microbes include various helpful & harmful bacteria, viruses, parasites, & fungi; so small you could fit millions through an eye of a needle and yet so powerful, any imbalance could cause a number of serious diseases to their host.
So far, microbiologists have discovered over 1000 different species of bacteria in human gut flora, containing over 3 million different genes (that's 150x more genes than humans have!).
One third of the discovered microflora are relatively common across the board, but two thirds are more specific to an individual, like a fingerprint. Despite the vast biodiversity possibly found in an individual's gut, only 150 - 170 species typically predominate in a single subject.
Science has proven these creatures play a pivotal role in regulating & enhancing the immune response, manufacturing neurotransmitters, essential short-chain fatty acids as well as vitamins (particularly B & K). They help with electrolyte absorption, suppressing inflammation, repairing intestinal permeability, and they can actually block pathogenic bacteria from adhering to the intestinal wall & making us sick. Due to the widespread effects on the entire body as well as directly producing neurotransmitters responsible for our mood, the gut & its inhabitants have been deemed, "the second brain".
The National Institute of Health (NIH) sponsors the Human Microbiome Project (HMP) to study the role of the gut microbiome indepth. They've shown that an imbalance in gut flora, also known as dysbiosis, is intimately linked to many gastrointestinal diseases, including ulcerative colitis, Crohn's, IBS, esophageal cancer, celiac disease, and other disorders such as type II diabetes, obesity, psoriasis, atopic dermatitis, and immuno-deficiencies.
They've also shown that dysbiosis is directly affected by poor food choices, emotional stress, lack of sleep, use of antibiotics & other drugs as well as environmental influences, like mold exposure.
Where They Come From
At birth, a human child is essentially sterile and obtains much of its microflora from its mother. Although a cesarean will rob the babe of beneficial microbes gained through vaginal birth, all is not lost; breast milk as well as skin-on-skin contact can also greatly benefit the baby, particularly in the first few days.
Lack of exposure to sufficient good germs during this time has been shown to increase risk of infection, allergies & auto-immune disorders.
Gut flora continues to establish itself throughout the early years, dependent mostly on the child's environment & the foods they're given. Eventually it stabilizes somewhat, but it's a jungle down there & your microbiome is always changing.
The term "probiotics" comes from the Greeks; meaning, for life, or life promoting.
It wasn't until the early 1900's when Ilya Ilyich Mechnikov (Elie Metchnikoff), the "father of probiotics" first discovered their benefits in sour milk. He theorized that health could be enhanced by manipulating the gut microbiome with host-friendly bacteria.
Good gut bugs are ideally obtained in your diet, most easily via home-made fermented foods such as, kimchi, sauerkraut, pickles, kefir, yogurt, kombucha, miso, tempeh, sourdough bread and many others. The fermentation process is induced by various microorganisms & enzymes that decompose organic substances into alcohols or organic acids (e.g. lactic acid) that in turn feed the many species of beneficial bacteria.
Helpful bacteria thrive in the gut on what the industry calls, "prebiotics"; which are simply non-digestible carbohydrates. Meaning, carbs that are resistant to human digestive enzymes. Also known as, fiber.
There are plenty of natural sources of "prebiotics" - including but not limited to:
apple, artichoke, asparagus, bell peppers, beets, broccoli, Brussels sprouts, cabbage, cauliflower, celery, chard, chicory, cucumber, dandelion, eggplant, garlic, green beans, kale, kohlrabi, leeks, lettuce, mushrooms, okra, onion, parsley, radishes, radicchio, spinach, turnip, watercress, zucchini.
Manufacturing & Supplementation
Found in food, capsules, tablets or powder form, we've seen widely growing popularity in the industrial manufacturing & supplementation of probiotics. Studies have shown they can play a role in obtaining some of our beneficial bugs, but you must know, they can also be harmful to your health. A word of caution to everyone who chooses to take these supplements, but especially small children, pregnant women, elderly people, and those with compromised immune systems.
For people with weakened immune systems, compromised digestion or leaky gut, taking a probiotic supplement may dramatically increase your chances of getting sick. Studies have shown that probiotic supplementation can cause sepsis (infection of the bloodstream) and other infections.
Another thing to consider is, compared to the 10's of trillions of microbes living in your gut and the thousands of different species possibly present, there are only a handful used in the industry. And much like calories, these microorganisms are not all created equal.
The genus, strain, and species must all be the same as those found in the study for one to claim the same beneficial results. For example, with the strain Lactobacillus rhamnosus GG, the genus is Lactobacillus, the species is rhamnosus, and the strain is GG. If any one of those are different, it's a completely differently bug.
Microbiologists have identified over 30 species of bifidobacteria and more than 50 species of lactobacilli.
Common strains found in supplements are:
Bifidobacterium bifidum, Bifidobacterium lactis, Bifidobacterium longum, Bifidobacterium breve, Bifidobacterium infantis, Bifidobacterium thermophilum, Bifidobacterium pseudolongum.
Lactobacillus acidophilus, L. acidophilus DDS-1, Lactobacillus bulgaricus, Lactobacillus rhamnosus GG, Lactobacillus plantarium, Lactobacillus reuteri, Lactobacillus salivarius, Lactobacillus casei, Lactobacillus johnsonii, Lactobacillus gasseri.
How They're Made
The requirements for a microbe to be considered a "probiotic" are: the microbe must be alive when administered, it must be documented to have a health benefit, and it must be administered at levels to confer with that health benefit.
For there to be any proven health benefits, the microorganism must be able to survive the manufacturing process, the storage period, the passage through the GI tract, it must also prove to stick to the intestinal wall & persist in the gut. That's hard to do in the lab.
Bacteria are sensitive creatures and could easily die in these harsh conditions. Live bacteria require careful preparation, monitoring, storage & combinations to ensure safety.
However, sudden freezing causes osmotic shock, which damages the cell wall & intercellular structures, rendering them useless.
To get around this, manufacturers coat the bacteria with a cryo-protectant (like a winter coat). This could be any combination of such things like, skim milk, dimethyl sulfate, glycerol, disaccharides such as sucrose, lactose, maltose & trehalose, bovine albumin (blood components of cows), wheat dextrin, maltodextrin, sodium ascorbate, glutamate, polydextrose, & polyethylene glycol.
To help the product have a fighting chance getting through the intestinal tract, many manufacturers store their probiotics with synthesized Vitamin C (ascorbic acid from corn syrup), a digestive enzyme &/or a "prebiotic".
Please Note: Probiotic supplementation may further pose a health concern if you are sensitive to the ingredients in any of their manufacturing methods. Read the ingredient label & check with the manufacturer if anything is unclear.
When & What To Supplement
There may come a time you find it necessary to beef up your gut flora, say, after a bout of diarrhea or before leaving on a month long trip around the world. As previously mentioned, good gut bugs are ideally coming from home-made fermented foods & a fiber-rich diet made up of organic, local ingredients.
But, with the growing popularity of packaged probiotics nowadays you can find a huge variety of supplements to choose from (again, please read the ingredients - some are just shit!). The most important thing is to determine what type of condition you're in & what type of microorganism will best suit it.
Bifidobacteria strains are considered to be the best biomarkers of intestinal health. These guys appear in the intestinal tract within days of birth, especially in breastfed infants, and set up shop mostly in the colon. Studies of Bifido strains have shown they can effectively alleviate IBS symptoms, distension/bloating, constipation, they can also help with glucose tolerance & blood lipid levels.
Lactobacillus are naturally found in the digestive, urinary & reproductive systems as well as in fermented foods, like yogurt. (Side note: all yogurt & fermented dairy products contain L. bulgaricus & Streptococcus thermophilus - don't be fooled by fancy marketing). Studies have shown some benefits linked to Lactobacillus strains treating &/or preventing yeast infections, urinary tract infections, irritable bowel syndrome (IBS), ulcerative colitis, diarrhea associated with antibiotic use, traveler's diarrhea, and diarrhea resulting from C. difficile infections. They can also help with treating lactose intolerance, skin disorders (fever blisters, eczema, acne, and canker sores), and respiratory infections.
Saccharomyces boulardii, or S. boulardii, is a form of yeast (which is a type of fungus). It is believed to be a strain of Saccharomyces cerevisiae (or, baker's yeast). Some studies have shown that it is effective in preventing & treating diarrhea of all sorts.
What To Look For
Probiotic strains used in supplement manufacturing should pass through a series of testing, including acid & bile stability, long-term safety and clinical validation of health claims. However, not all supplements are monitored the way other food & drug products are. Dietary supplements and ingredient manufacturers are responsible for their own products safety testing before it is marketed. There is no governing body overseeing the validity of their health claims or the methods used to conduct them. False claims and faulty methods are common, so for this and other reasons, it's important to choose manufacturers who opt for third party testing.
Other important criteria to ensure you're getting a quality probiotic:
Please note: Probiotic supplements should not be taken as a replacement to a proper diet or in place of disease-specific medication.
Dysbiosis has been directly linked to poor food choices, emotional stress, lack of sleep, prescription drug use as well as environmental influences, like mold exposure. You are urged to address these things naturally before you attempt to adjust your microbiome with industrial supplements. If you are considering supplementation, please consult with a qualified health-care provider & do your research to be sure there are scientific studies to support what you're taking.
About the Author:
Before Megan pursued a career as a Registered Holistic Nutritionist, she studied molecular biology, biochemistry and pharmaceutical chemistry at the University of Guelph. She had the privilege to work for major pharmaceutical & biotech companies on projects involving calibration, DNA preparation, and creating standard operating procedures. Now, she trusts cows over chemists & uses her kitchen as her laboratory where she teaches curious folks how to get to the root cause of their health concerns, naturally.
Capela, P. Hay, T.K.C. Shah, N.P. (2006) Effect of cryoprotectants, prebiotics and microencapsulation on survival of probiotic organisms in yoghurt and freeze-dried yoghurt. Food Research International. 39(2): 203-211
Saarela, M. et. al. (2005) Influence of fermentation time, cryoprotectant and neutralization of cell concentrate on freeze‐drying survival, storage stability, and acid and bile exposure of Bifidobacterium animalis ssp. lactis cells produced without milk‐based. Journal of Applied Microbiology, 99 (6), 1330-1339.