The Role of Probiotics in Gut Health and Digestive Wellness

The gut microbiota is vital for a healthy digestive process, nutrient absorption, and immune function. Probiotics act as reinforcements for the natural bacteria and improve digestion by reducing strains of pathogenic bacteria, stimulating the immune system, and improving the mucosal barrier.

Saccharomyces boulardii (a yeast) and Lactobacillus species, such as LGG, have been shown to have health benefits including the treatment of diarrhea. But, not all probiotics are created equal.

Benefits

The microorganisms that live in your gut—the gut microbiota—play a role in many aspects of health. These bacteria support your immune system, regulate metabolism and even influence brain functioning. In fact, research has now found a direct link between the digestive tract and your mental state, known as the gut-brain axis.

Probiotics have been shown to improve a range of health symptoms, including irritable bowel syndrome, constipation, anxiety, high blood pressure, depression and yeast infections. They also help reduce inflammation and increase the absorption of vitamins, minerals and phytochemicals.

One of the most common probiotics is the lactic acid bacteria (LAB) Lactobacillus. LAB are often used as probiotics because they can survive the stomach acids and travel throughout the digestive tract. In addition, LAB can produce unique metabolites that inhibit the growth of harmful organisms and support normal intestinal function. Recent studies have shown that the bacterium Enterococcus genus (EcN) can deliver a wide range of health benefits, including improving cholesterol levels and controlling blood pressure. EcN has also been engineered to secrete antimicrobial substances that can prevent infection in mice.

Symptoms

Probiotics help improve digestion by enhancing gut lining strength, making it easier to absorb and digest vitamins, minerals, amino acids and fats. They also help train the immune system to recognize and eliminate pathogens.

A lack of these beneficial bacteria has been linked to poor digestion, diarrhea and irritable bowel syndrome. Probiotics have also been shown to reduce allergies and eczema.

Probiotics inhibit the growth of pathogenic microorganisms by preventing them from adhering to epithelial cells, secreting antimicrobial substances and blocking their access to nutrient resources. Moreover, they can prevent the proliferation of pathogens by increasing cell death or stimulating phagocytosis. They can also stimulate innate immunity by triggering the production of certain immune cells such as CD4+ T lymphocytes and B cells. They can even increase your body’s level of immunoglobulin A (IgA), a key antibody that fights bacterial infections.

Diagnosis

Probiotics are live microorganisms that contribute to the populations of beneficial bacteria in your gut and other parts of your body. They help prevent and treat diseases caused by imbalances or deficits of these bacteria.

Probiotic bacteria produce compounds that stimulate the growth of other microorganisms or turn on the immune system to defend against pathogens. This is how they help alleviate symptoms like diarrhea, constipation or stomach pain.

The probiotic strain Escherichia coli Nissle 1917 (EcN) was isolated by army surgeon Alfred Nissle in World War I from the stool of an ill soldier. EcN is a Gram-negative bacteria that is safe and effective at inhibiting antibiotic-associated diarrhea.

EcN is also being engineered to secrete cytokines for the purpose of preventing HIV infection. Its ability to colonize the intestinal mucosa for weeks to months makes it a superior candidate for delivery of cytokines and protein vaccines. It has also been shown to significantly reduce symptoms of vulvovaginal candidiasis.

Treatment

As the probiotics field expands, researchers have discovered that different strains of bacteria can provide distinct benefits. Stool tests such as the Genova Diagnostics GI Effects Comprehensive Profile can help identify a patient’s specific needs and target the most helpful probiotic supplements.

For example, Saccharomyces boulardii can increase SIgA production in the gut and improve intestinal barrier function, reduce inflammation, support immune balance, and has antimicrobial effects by decreasing bacterial adhesion to mucosal cells.

The brain-gut-microbiome axis also influences mood, and low probiotic levels can result in lower serotonin and higher cortisol (stress hormone). This may explain why depression and anxiety can be signs of gut dysbiosis.

Another promising area of research is the creation of probiotics that produce specific cytokines. For instance, genetically engineered Lactococcus lactis has been shown to secrete IL-10, heme oxygenase 1, trefoil factors, and Yersinia protein LcrV. These peptides are directly delivered to mucosal cells, preventing the colonization of pathogens and establishing tolerance.