Within our guts are trillions of bacteria that we now understand to have a tremendous impact on our health, as well as a role in disease. Having many diverse and different kinds of bacteria living within the gut is associated with human health. Disruption of this delicate ecosystem and a loss of diversity have been linked to numerous diseases, including allergies, asthma, infections, obesity, constipation, diabetes, irritable bowel syndrome (IBS), inflammatory bowel diseases (IBD), and colon cancer. Research aimed at understanding the link between gut microbes and human health has great potential to identify new ways to improve human health by altering the gut microbiota.

Probiotics are defined as live microorganisms that when taken confer a health benefit. Probiotics can be taken as dietary supplements in the form of capsules, pills, or powders, or can be obtained through fortified yogurts and other foods, as well as fermented milk products. There are many different types of probiotics, but the most commonly used organisms include strains of Lactobacillus and Bifidobacterium.

Probiotics act through many different ways, including stimulating the immune system, helping maintain a strong gut barrier function, displacing pathogens, and modulating the nervous system. Benefits of probiotic health supplements appear to reach far beyond simply gut health. Some of the well-researched uses of probiotics in gut health include infectious diarrhea, antibiotic-associated diarrhea, prevention of C. difficile associated diarrhea, and irritable bowel syndrome. In addition to improving digestive health, research has shown benefits in immune health, preventing common infectious diseases, lowering fasting blood sugar in Type 2 diabetics, lowering bad cholesterol, and preventing eczema.

Probiotics can be taken to help maintain a balanced gut microbiota, as well as used to help in the treatment of certain digestive conditions. However, it is important that the proper strain of probiotic be taken for the appropriate condition. For instance, Lactobacillus GG has been shown to be effective in preventing antibiotic-associated diarrhea, while Bifidobacterium longum infantis 3562 has shown effectiveness in not only relieving gut symptoms of irritable bowel syndrome but also improving depression and quality of life in these patients. Indeed, several recent research findings have shown probiotics to alter brain function in individuals. Although more research is required, these fascinating observations suggest that microbes in our guts can have far-reaching effects throughout the body.

An excellent resource for patients and physicians looking for advice on which strains to use for what conditions can be found on the website Clinical Guide to Probiotic Products at probioticchart.ca. This website is updated annually and provides information regarding what evidence exists for specific products and for what indications. It is a reliable tool that can help both consumers and health care professionals navigate through the wide variety of probiotics available commercially.