Since your gut contains hundreds (if not thousands) of different types of bacteria, it’s best to find a probiotic that contains a wide variety of bacterial strains. Most probiotics will include the 2 major strains Lactobacillus acidophilus and Bifidobacteria bifidum.
These two strains are important because different bacteria adhere to different areas of the digestive and intestinal tract.
For instance, lactobacilli bacteria have an affinity for the upper GI tract, namely the alkaline medium in the small intestine. Bifidobacteria tend to favour the slightly more acidic environment of the large intestine. Thus, it’s important to get the best of both of these bacteria and numerous species and strains that they encompass.
Normal, healthy colonies of lactobacilli and bifidobacteria can help maintain a healthy balance of intestinal microflora. Many probiotics may disintegrate prematurely when exposed to stomach acid so they never reach the lower intestine. I have found Shaklee's Optiflora has a state-of-the-art, triple encapsulated, seamless capsule that is guaranteed to withstand the acidic environment of the stomach to deliver live beneficial bacteria to the intestine.
For further reading on this topic see the below article:
Probiotics
The body's immune booster and regulator
As you may know, the human digestive tract is filled with bacteria. In fact, the whole human body contains more individual bacterium than actual human cells. Most of the bacteria in the digestive tract are beneficial and promote a symbiotic relationship within the body. The exception to the rule is foreign, illness-causing bacteria. Essentially, gut microflora (bacteria) is what allows the digestive system to function as it does. Among its many tasks, these live microorganisms aid in fermenting (and utilizing) carbohydrates, aid the body in absorbing nutrients from food, and boost immunity within the body.
Where to Find Them
Probiotics aren’t as elusive as they sound; they’re attainable in fermented foods such as yogurt, soy yogurt, pickled vegetables, kefir, buttermilk, tempeh, miso soup, and even sauerkraut. Since these foods make up only a small portion of the average person’s diet, supplements have taken center stage as a means to boost the number of probiotic bacteria within the gut.
You may ask yourself why humans need to ingest probiotics if they already exist within our intestinal tract. The body does not make probiotics on its own; they must be consumed through diet. However, a modern diet consisting of heavily processed, preserved, and nutrient-deficient foods does not provide plentiful probiotics for consumption. In addition, antibiotics, frequently prescribed for common ailments, and pesticide-laden GMOs, are notoriously known to kill probiotics and create an imbalance of bacteria in the gut.
What Probiotics Are
Probiotics are bacteria present in the intestinal tract that are defined by the Food and Agriculture Organization (FAO) and World Health Organization (WHO) as “live microorganisms which when administered in adequate amounts confer a health benefit on the host.” This is a broad definition, but in terms of probiotics, there are a wide variety of “good” bacteria to include in your diet.
Different Types
Probiotics is an umbrella term that covers several strains. Lactic acid bacteria (LAB) Lactobacillus and Bifidobacterium are the two principal genuses of probiotic bacteria. Lactobacilli reside in the small intestine, while bifidobactiria are active in the colon. Probiotics are identified by genus, species, and strain. Here are some common probiotic species and strains (of the Lactobacillus and Bifidobacterium genus) that may be found in food or supplements and what their role is within your gut:
Lactobacillus:
Most probiotic strains belong to the genus Lactobacillus. Probiotics have been evaluated in research studies in animals and humans with respect to antibiotic-associated diarrhea, inflammatory bowel disease, and irritable bowel syndrome (IBS). It is possible that, in the future, probiotics will be used for different gastrointestinal diseases, or as delivery systems for vaccines.
>> L. acidophilus CL1285 (a strain of Lactobacillus) is used in the production of yogurt—it’s one of the “live and active cultures” you may see printed on the side of the yogurt container. Its purpose in yogurt is to decrease pH of the milk used to create yogurt. Since L. acidophilus can survive pH levels of four to five or below, it can pass through the acidic environment of the stomach into the small intestine and work its magic in keeping intestines clean and boosting the immune system.
>> L. reuteri DSM 17938 is often used as a dietary supplement as it boosts the immune system and simultaneously attacks foreign pathogens in the gastrointestinal tract.
>> L. rhamnosus GG is also used in the production of yogurt and some other dairy products. It inhibits pathogen growth in the urogenital tract, inhibits diarrhea from the rotavirus, and oddly enough, has been shown to reduce anxiety in lab mice.
>> Lactobacillus casei produces a carbohydrate-digesting enzyme known as amylase, which is essentially the beginning process of digestion for all foods. Without amylase, food could literally pass right through you.
Bifidobacteria:
>> Bifidobacterium lactis is known to prevent diarrhea, reduce colon inflammation, and provide relief from constipation.
>> Bifidobacterium animalis shortens colonic transit time, that is, how long it takes for a meal to be digested and eliminated by the body through a bowel movement. Bifidobacterium animalis also plays a role in processing B-complex vitamins.
Health Benefits
Probiotics tout numerous health benefits—even for a relatively healthy individual or a person in excellent health, probiotics maintain health. Yet the use of probiotics for those who suffer from various ailments is becoming more widely recognized as more research is done.
Inflammatory bowel disease (IBD) is a painful condition caused by inflammatory changes in the colon and intestines. It has been noted that people with IBD have a different composition of gut microflora than healthy individuals; they lack the probiotics bifidobacteria and lactobacilli.
Individuals who are lactose intolerant may drink sweet acidophilus milk (also made from L. acidophilus) as it allows the stomach to easily digest the enzymes present in dairy. L. acidophilus has also been shown to boost the immune system by increasing cytokine, phagocytic activity, and antibody production. Another important aspect of L. acidophilus is that it is present in normal vaginal flora. There are various causes for an alteration in vaginal flora such as antibiotics, other medications, stress, or even chemicals from laundry detergent that lead to a proliferation of Candida albicans (more commonly known as a yeast infection).
According to a 2011 study published by the Public Library of Science, L. ccasei DN-144 001 improves symptoms of colitis by strengthening the gut barrier function. This is also true of L. ccasei DN-144 001 for cases of inflammatory bowel disease (IBD), Crohn’s disease, and ulcerative colitis.
Probiotics and calcium work together—probiotics boost calcium absorption, and calcium aids the effectiveness of probiotics. You may see why yogurt is an ideal food for probiotic delivery. In addition to increasing bioavailability of minerals, probiotics break down fats from food (known as lipolysis) and convert lactose to lactic acid.
