When you shop for probiotic supplements, you’ll likely see that the product contains a billion or more colony forming units (CFUs), or the number of cells that are viable. But what are these bacteria that are critical to having a healthy gut? And does it matter what the cocktails of microorganisms consists of? We’ve compiled a primer of what science and research says about how specific groups of microbes can benefit the human gut. Keep in mind that supplements aren’t the only way to balance your gut. Check out our gut diet for a list of both probiotic and prebiotic foods. But sometimes you need a power boost to get your microflora balanced out. Here are eight probiotic groups that have been studied for their positive effect on the human gut.

Lactobacillus

Arguably the most well-known probiotic group, Lactobacillus contains 25 genera and many species which are gut positive. Studies have shown that Lactobacillus inhibits the growth of Candida albicans, a fungal pathogen, and can help to prevent antibiotic-associated diarrhea. This group of bacteria is also used as a starter culture for some of the most popular foods including yogurt, cheese, pickles, kimchi, beer, wine, cocoa, and sourdough.

Bifidobacterium

Right up there with Lactobacillus, Bifidobacterium is a common microbe used in probiotic supplements. Bifidobacterium colonizes the human gut, as well as the oral cavity and the vagina. There are many strains of this bacteria that function as probiotics including B. bifidum, B. longum, B. breve, Bifidobacterium infantis, B. adolescentis, and B. animalis. Bifidobacterium has been shown to help to treat antibiotic-associated diarrhea, traveler’s diarrhea, constipation, as well as reduce the severity and inflammation associated with ulcerative colitis. Other studies have demonstrated the potential application of Bifidobacterium in lowering cholesterol and decreasing the risk of developing food allergies and eczema.

Akkermansia

Described as a next-generation probiotic, there are only two species of Akkermansia that have been identified. Scientists have focused on Akkermansia’s ability to affect human metabolic function, including lipid and glucose metabolism, as well as its ability to reduce obesity, diabetes, and inflammatory processes.

Saccharomyces

Saccharomyces is a group of fungi that includes yeasts, such as brewer’s or baker’s yeast. This microorganism is also used in the production of wine, bread, beer, kombucha, and kefir. Various clinical studies and research have demonstrated that the strain Saccharomyces boulardii is effective in decreasing the duration of diarrhea, regardless of causative factors. It has also been studied for its benefits in treating irritable bowel syndrome, inflammatory bowel disease, and ulcerative colitis.

Bacillus, Streptococcus and Enterococcus

It may come as a surprise to most people that not all strains of Bacillus, Streptococcus and Enteroccocus are bad for you. Streptococcus conjures up images of strep throat, scarlet fever, cellulitis, and impetigo, while Enterococcus causes urinary tract infections and meningitis. And Bacillus anthracis and Bacillus cereus are responsible for anthrax and food poisoning, respectively. But there are strains of each that have positive effects and are considered probiotic including Bacillus coagulans, Streptococcus thermophilus and Enterococcus durans. Bacillus coagulans, specifically, has been studied for its ability to reduce abdominal pain and bloating associated with irritable bowel syndrome, and is being investigated as a possible intervention for diarrhea caused by Clostridium difficile.

Escherichia coli

Another microorganism thought of as universally bad, the list of diseases caused by E. coli is a long one – urinary tract infections, pneumonia, bacteremia, cholecystitis, and of course, traveler’s diarrhea. But one strain in this genus has been found to exist. Escherichia coli Nissle 1917 (EcN) has been clinically demonstrated to alleviate constipation when paired with other probiotics and has also been investigated as a therapeutic in the treatment of ulcerative colitis, inflammatory bowel disease, and Crohn’s disease. There’s always at least one good egg in a family.

Our product choices for probiotics:

• Plexus ProBio5. This powerful supplement contains five beneficial probiotics — Lactobacillus acidophilus, Bifidobacterium longum, Lactobacillus plantarum, Bacillus coagulans, and Saccharomyces boulardii, at 2 billion CFUs per capsule. Added bonus is the enzyme blend of proteases, cellulase, and serrapeptase that supports digestive health. Shop it at PlexusWorldwide.com
• Plexus Slim Microbiome Activating. This product takes a prebiotic approach to supporting gut health, by providing xylooligosaccharides to nourish key probiotics Lactobacillus and Bifidobacterium. It also increases the population of Akkermansia, meaning it increases metabolism. Shop it at PlexusWorldwide.com