Probiotics and Prebiotics. Did You Eat Your Bacteria Today?

**rmkicks** · 02-20-2014, 11:58 AM

Getting sick sucks. Have you ever gotten sick just before a show? How about afterwards? How about when you ate the same food for 10 weeks before a competition and for some “strange” reason you started to get bloated, nauseated and maybe even collected a few “tales of the strange” with your gastrointestinal system?
Well, “strangely” enough, “bugs” might be to blame here. It could be a bad bug that caused a bacterial infection, or perhaps a lack of the good “bugs” that help keep your immune system running strong. Note here that when I say “gut” I don’t mean the belly you slap after a finishing post-show binge or your Uncle Bill’s gravity-defying abdominal monstrosity. I’m referring to lumen of your digestive tract, starting with your mouth and ending in your nether-regions. This entire tube (the alimentary canal) is actually outside your body, just like your skin and even the inner lining of your lungs (1).
You’re a Bug Factory

Since they are on the front when it comes to infectious invaders, our skin forms a (relatively) thick protective barrier and our lungs produce mucus to trap the foreign particles before ejecting them with a sneeze or cough. A much more impressive strategy, and unbeknownst to you perhaps, is that nature has actually paired us up with good-guy bacteria that live and thrive in our gut. These bugs aren’t just parasitic free-loaders though; they live symbiotically, and many of them commensally, in our gut. This means that they provide specific advantages to our normal physiological function. These bacterial belly buddies, especially those in your colon, reside in close proximity the immune system’s lymphatic tissue, most of which is actually part of the GI tract (2, 3). That’s right, most of the lymphatic tissue of your immune system is in your gut.
We’re not just talking about a few bacteria scattered here and there. There are approximately 100 trillion microorganisms, collectively known as our microbiome (4), hitching a ride within each of you reading this. Most of the microbiome are gut bacteria, called the “microbiota.” If that sounds like it a lot…well, it is. The total number of cells in our body is just about 37 trillion (5) and the human population of the entire world is just about 7.1 trillion (as of now (6)). In fact, the gene pool of the microbiome is more than a hundred times larger than the human genome (3). You have an entire genetically diverse “world” of beneficial bacteria living in your belly.
Bugs and Bug Food: Probiotics and Prebiotics

The wanted gut bacteria, specifically those in the colon (large intestine) (7), aid in immune function, processing of food and even vitamin absorption, in addition to helping ward off pathogens (3). Of these, the lactic acid bacteria — Lactobacillus and Bifidobacterium genera — are the best studied (3, 8-10). These helpful bacteria are called probiotics and require non-digestable food components (typically fibers such as fructooligosaccharides and inulins) to grow and prosper. The probiotic food sources are known as prebiotics (11), although this definition is (as scientists like to do) somewhat debated (12, 13). Postbiotics refer to the substances produced by probiotic bacteria that have healthful function (14). Health supplements that combine pre– and probiotics are called synbiotics (12, 13), and may often have superior health benefits compared to probiotics alone (10, 15).

Good Buggie-Bugs

Probiotics protect us in a multitude of ways. Below are some potential unwanted circumstances in the large intestine and what probiotics do for us [adapted from Gibson et al. (7)]:

Unwanted Event	Probiotic Benefit
Toxin Production (via Digestion)	Immune System Stimulation
Diarrhea / Gas	Less Gas and Distention
Carcinogen Exposure	Breakdown of Procarcinogens
Gut Infections	Inhibition of Invading Species
Inflammatory Bowel Disease	Production of Butyrate(16)
Liver Stress	Breakdown of Xenobiotics/Toxins
Antibiotic-associated Infection	Reduce unwanted bacterial “translocation”

Not surprisingly, probiotics have shown promise in treating issues like antibiotic-associated gastrointestinal problems (e.g., diarrhea) (17), ulcerative colitis (10, 15), irritable bowel (18, 19), colon cancer, diabetes, food allergies (12), lactose intolerance (20), respiratory infections (12) and even cardiovascular disease (21, 22).
How do they do it?

In keeping the gut healthy, the immune cells there can effectively scan for toxins, foreign invaders. This in turn bolsters immune responses via a common (mucosal) immune system that’s interconnected with the lungs and uro-genital tract (23-25). This is a huge part of our body’s overall (humoral) immunity, as the immunoglobulin IgA is the major one secreted in the gut (26). IgA is also the immunoglobulin secreted in the largest quantities by the body (27), with daily production exceeding that of all other immunoglobulins combined (3, 28). That is a big deal when it comes to fighting the nasty bugs.
Probiotic PotLuck

As one might expect, these probiotic armies also produce their own metabolic “waste products,” but these metabolites are actually “regifted” back to the host (you and me). Believe it or not, up to 30 percent of our daily energy requirements may come from probiotic breakdown products, which is enough to affect weight gain or loss (29, 30). In particular, short chain fatty acids (SCFA) like butyrate produced by probiotic bacteria (3, 31) are re-absorbed back into the bloodstream where they also exert a wide range of physiological effects. Science is just starting to dig into it, but it’s clear that our diet can change the gut microbiota, which can impact energy balance and weight gain or loss (32).
SCFAs are more than just fuel. For instance, the SCFA propionate and its derivatives promote a healthy cholesterol profile (31, 33), are involved in leptin production (29, 34) and have anti-inflammatory effects (35). On the other hand, protein that makes its way to the large intestine has long been known as a source of toxins and even carcinogens (31) after being acted upon by bacteria there. This aspect of intestinal bacterial metabolism is largely undiscovered, too, even though it may potentially contribute to symptoms like depression, sleeplessness, vomiting, headaches, and even skin diseases (31, 36, 37).
Okay, so what do I eat?

Foods that provide prebiotics (“bug food”) include legumes, vegetables (onions, asparagus, and garlic especially), cereals (wheat, barely and rye), fruits (banana, tomatoes) (38), and raw honey (39). Probiotic bacterial growth and metabolism may even differ depending on the source of the honey (40). Chicory root (when roasted) can be used to brew tea and is the primary source used for prebiotic supplements as it is very high in inulin (41, 42).
Probiotic foods are typically those that have been fermented (43) (an anaerobic process in bacteria, converting carbohydrate into alcohol, carbon dioxide and/or lactic acid), and are found in cultures (pun intended) around the world (44). Bacterial “starter cultures” containing Lactobacillus and Bifidobacterium are used most often to create these products commercially (43). Dairy-based products include yogurt (including Greek yoghurt, which is high in protein), kefir, and aged and cottage cheese (43). Frozen yogurt may be unlikely to contain active cultures, unfortunately (45), which saddens me greatly. Other fermented foods like kimchi (46), sauerkraut (47), miso soup (48), pickled vegetables (49-51), and, my favorite, kombucha tea (52, 53) are easy to find, too.

So, how soon will I FEEL it?

Direct studies on exercise performance (ergogenic effects) are lacking (54), but a strong (perhaps even obvious) argument from the available evidence suggests that a healthy microbiome and probiotic supplementation can reduce negative impact of intense training (25, 55) on respiratory infections and gastrointestinal disturbances (56, 57). If you’re getting sick and/or are having GI problems on a regular basis, but almost never eating probiotic-containing foods, this may be a solution. I personally have a tendency to get sick shortly after a competition. Specific probiotics like Lactobacillus Acidophilus may also prevent food poisoning (58), which seems to be a common issue with weary pre-contest bodybuilders competing far away from home.
It has been suggested that it may take at least a couple weeks (with regular supplementation) for beneficial effects to manifest (55). Eating pro- and prebiotic foods on a consistent basis would be my general suggestion because they often contain a variety of probiotics (43). Of course, pre-, pro- or synbiotic supplements [e.g., 1-2g inulin with a probiotic labeled to have a colony forming unit (CFU) count in the 10 billion range] can be quite effective, too (25, 59). Unfortunately, it is very common that probiotic supplements are mislabeled or contain no probiotic strains at all (60, 61), and some may even contain harmful bacteria (62). Note also that it’s not uncommon to experience gastrointestinal upset when adjusting a new probiotic supplement (63). If in doubt or if you suspect a medical issue, consulting with a licensed professional who can interpret a stool analysis would be the way to go in fine-tuning your probiotic regimen.
If you’re sick of getting sick and pooped because you’re not poopin’ good, regularly befriending a few billion probiotic bacteria (and keeping them well fed) may be all it takes for happier, healthier days filled with heavy and hard training.