The vast range of beneficial bacterial species now available to consumers in probiotic supplements can present a challenge when choosing a specific product for purchase. When various species of probiotic bacteria provide particular health benefits, it can be extremely difficult to know which blend of species best fits each person’s unique health needs.
Even within specific genera of bacteria, such as the Bacillus genus, hundreds of species have been named so far (a total of 266 species, to be exact). These species can be found in a wide variety of locations, such as soil, air, water, vegetables, food, as well as the guts of both humans and animals. Some of these species are used in Bacillus probiotics and may have benefits for digestive, immune, and full-body health. In contrast, others, such as Bacillus cereus, may be pathogenic (illness-causing) and lead to health problems such as food poisoning.
A notable feature of Bacillus species is that they are spore-forming, which means that they are able to create outer shells around themselves and go dormant to withstand extended periods of food deprivation, dryness, and heat/cold. These endospores, as they’re often known, are also resistant to conventional disinfectants. Although endospore formation can be problematic when dealing with pathogenic bacteria, this mechanism may allow Bacillus probiotics to resist stomach acid, which is thought to allow more beneficial bacteria to reach the small intestine and colon.
Which Bacillus Species Are Used as Probiotics?
With hundreds of species of Bacillus being available, it can be difficult for those seeking to improve their health to choose the best probiotic with Bacillus strains for their needs.
Some of the most common and well-studied Bacillus species include B. cereus, B. pumilus, B. subtilis, B. coagulans, and B. polyfermenticus. Following is an overview of these species to better understand their unique attributes and benefits.
Bacillus Coagulans Strain
Now officially known as “Weizmannia coagulans,” but often referred to as Bacillus coagulans, this bacterium is generally thought to produce copious amounts of lactic acid.
Bacillus Coagulans Benefits
coagulans have been shown to improve symptoms of constipation and irritable bowel syndrome (IBS). Additional benefits of Bacillus coagulans may also include improved digestive symptoms (e.g., diarrhea, indigestion, etc.), modulating immunity, repair of the gut barrier, and help to regulate gut microbiota with the production of antimicrobial compounds (bacteriocins and lipopeptides).
Bacillus Subtilis Strain
Also known as the “hay bacillus” or “grass bacillus,” probiotic Bacillus subtilis is also a spore-forming species. In the wild, it is commonly found in soil as well as the digestive tracts of humans, ruminants, and marine sponges.
Bacillus Subtilis Benefits
Bacillus subtilis’ probiotic benefits are thought to be abundant and have been established as such in scientific studies.
For instance, a particular 2022 study utilized a randomized, double-blind, placebo-controlled trial and was designed to be highly rigorous to make its results more reliable and accurate. The study found that daily supplementation with a particular strain of B. subtilis probiotic (BS50) for six weeks improved symptoms of abdominal bloating, burping, and flatulence compared to the placebo group. A separate study found that B. subtilis CU1 supplementation enhanced immune responses in older adults. These promising study results are consistent with what is thought to be the benefits of many Bacillus probiotics for digestive and immune health.
Bacillus Clausii Strain
Now named “Alkalihalobacillus clausii” (but still frequently referred to as Bacillus clause), this species is typically found in soil, as well as the GI tract of most mammals.
Bacillus Clausii Benefits
Bacillus clausii health benefits are thought to be numerous. A systematic review of clinical trial data shows that this species can be a particularly effective treatment for acute and chronic diarrhea. Bacillus clausii probiotics may also have antimicrobial and immunomodulatory effects due to the bacterium’s production of substances that may kill pathogenic gram-positive bacteria, such as Staphylococcus aureus and Clostridium difficile. Supplementing with Bacillus clausii bacteria may also help to prevent respiratory infections and treat small intestinal bacterial overgrowth (SIBO).
Bacillus Pumilus Strain
Bacillus pumilus is most commonly found in soil and water and is often sprayed on crops to prevent the growth of fungal pests and nematodes. It is also known to be used in the production of enzymes for industrial purposes. It has even survived in the vacuum of space for 18 months, making it one of the most resilient bacteria known.
Bacillus Pumilus Benefits
There are relatively few studies of Bacillus pumilus as a probiotic in humans. Considering its GI and immune benefits in animals (such as a study showing that it may reduce intestinal inflammation and injury in poultry), it may have potential as a probiotic for human consumption in the future.
Bacillus Polyfermenticus Strain
In Japan and South Korea, Bacillus polyfermenticus has been used to help treat intestinal disorders for quite some time. Although it is often used in Japan and South Korea, this species is less commonly used in probiotics in the U.S.
Bacillus Polyfermenticus Benefits
Similar to other Bacillus probiotics, Bacillus polyfermenticus may have promising benefits for digestive health. A study evaluating its probiotic potential concludes that B. polyfermenticus could have probiotic benefits in both animals and humans. In a small study of human subjects, the bacterium has been shown to affect immune function positively. In a study of mice with colitis, Bacillus polyfermenticus was shown to reduce colonic inflammation. It has also been demonstrated to have a potential anticancer effect, inhibiting the growth of colon cancer cells in vitro (in a petri dish). But more studies are needed to understand the specific benefits of B. polyfermenticus.
Which Bacillus Is Best for Gut Health?
The science of the microbiome is relatively new, and the manner in which probiotics interact with the human gut and immune system are incredibly complex, so it is nearly impossible to definitively state which Bacillus species may offer the most benefits for gut health.
Discovering the answer to this question will require additional well-designed scientific studies to compare the effects of specific Bacillus species on human health. In the meantime, taking probiotics that contain the Bacillus species with the most demonstrated benefits, which are rooted in scientific studies, is the wisest approach to probiotic supplementation at this time.
The Best Probiotic: Body Kitchen Gut Balance
Body Kitchen Gut Balance probiotic contains six billion colony-forming units (CFU) from three live strains discussed above, including: B. coagulans, B. subtilis, and B. clausii. These strains may help to repopulate beneficial bacteria in the colon. They may even improve digestion, while reducing unpleasant symptoms such as gas, bloating, and constipation while promoting improved nutrient absorption during digestion. Body Kitchen Gut Balance may help to enhance the gut’s response to inflammation in as little as 12 weeks.
Also included in Body Kitchen Gut Balance is MicrobiomeX®, a clinically studied blend of flavonoids derived from orange and grapefruit that may help shift the composition of the gut microbiome toward a higher ratio of beneficial bacteria. This may help improve gut barrier function and have antioxidant and anti-inflammatory effects in the gut and overall system.
One of the essential attributes of Body Kitchen Gut Balance is that its scientifically studied ingredients are included at the correct (i.e., clinically effective) doses that have been shown in studies to be beneficial. This means that those who take Body Kitchen Gut Balance regularly consume clinically studied ingredients at clinically studied doses.
Before adding a probiotic to your supplement routine, be sure to speak with a physician who is familiar with your medical history. Those with immune system issues (such as people who are medically deemed as immunocompromised), those who have undergone surgery, and those who are critically ill may be more likely to have negative health issues as a result of taking probiotics.