Episode #157: The COMPLETE Guide to Probiotics Featuring Kiran Krishnan!

Dylan Jarmeli welcomes back Dr. Kiran Krishnan, a renowned microbiologist and Chief Scientific Officer at Just Thrive, for an in-depth discussion on the complete guide to probiotics. This episode is the first in a series dedicated to understanding gut health and its profound impact on overall well-being. Dr. Krishnan emphasizes the importance of focusing on key components and aspects of gut health, promising a selective yet comprehensive exploration of various topics related to the gut.

Understanding Probiotics, Prebiotics, and Postbiotics

Dr. Krishnan begins by clarifying the definitions of probiotics, prebiotics, and postbiotics, as defined by the World Health Organization. A probiotic is a live microorganism that, when administered in adequate amounts, confers a health benefit to the host. This means a true probiotic must be alive and functioning in the living state in the gut, surviving the gastric system and small bowel to reach the intestines. Furthermore, it must have a dose-dependency, meaning specific studies should show its effectiveness at certain dosages, and it must confer a measurable health benefit.

Prebiotics are essentially food for microbes. These are typically complex carbohydrates found naturally in fruits, vegetables, and starchy foods like cassava and potatoes. Prebiotics cannot be absorbed or broken down by humans, meaning they pass through the small bowel into the large bowel, where they specifically feed beneficial bacteria.

Postbiotics are defined as dead bacteria that still possess functionality, or a component of a bacterium. Dr. Krishnan explains that research over the last 15-20 years has shown that some microbes, even when dead, can provide similar benefits to live microorganisms. This is because specific components on the outer cell structure or membrane of the microbe are responsible for signaling and performing the beneficial work, negating the need for the microbe to be alive.

All three—probiotics, prebiotics, and postbiotics—can be utilized to improve gut health, but they play distinct roles. Dr. Krishnan suggests that if one had to choose only one, the probiotic would be the most important, as it can influence prebiotic-like effects by enhancing the fermentable capabilities of existing gut microbes and provide postbiotic-like effects by increasing the growth of certain beneficial microbes.