About The Buzz: Healthy Individuals Don’t Benefit from Probiotics?

About The Buzz: Healthy Individuals Don’t Benefit from Probiotics? Fruits And Veggies More Matters.org

TheBUZZ Healthy Individuals Don’t Benefit from Probiotics?


Probiotics are all the rage these days, but is this type of supplement actually helpful? New research demonstrates there is little evidence to back up claims that probiotics promote gut health in healthy adults.1


Within every human being resides a unique microbiome, or the community of microorganisms that inhabit our bodies, creating a mini eco-system type space.2 The term microbiota refers to the clusters of bacteria that reside in specific areas of the body – for example, your skin microbiota, oral microbiota, gut microbiota, etc. Bacteria residing in the gut (or “gut flora”) partake in several life-sustaining functions: fermentation of indigestible dietary fibers, synthesis of vitamins and amino acids, regulation of the immune system and regulation of gastrointestinal hormone release.3 There are several types of bacteria – symbiotic, commensal and pathogenic.2 Symbiotic bacteria offer a mutually beneficial relationship, commensal bacteria are neutral, and pathogenic bacteria may cause disease.

Everything you do impacts your body’s microbiome, from eating a meal to kissing a loved one, applying cosmetics, petting an animal (and cleaning up after your pet!), using a public toilet or cart at the grocery store – every action you undertake introduces new bacteria from your environment to your body’s microbiome. Your gut’s health, or lack thereof, has a profound impact on the health and wellbeing of your entire body.


Probiotics are live organisms (bacteria) that help to repopulate intestinal bacteria when administered in adequate amounts. Probiotics support the symbiotic bacteria and help keep the gut flora balanced. Probiotic foods are typically fermented, such as yogurt, soft cheeses, miso soup, sauerkraut, kefir, tempeh, kombucha, buttermilk and pickles.2 While there is much evidence to support probiotic supplementation for a broad range of diseases, the research on the effect of probiotic supplement use in healthy individuals has not been explored.


Due to the recent emphasis on gut health and probiotics, it’s important to understand what the current research shows before you purchase any probiotic supplements. A recent review, published in Genome Medicine, summarizes the research to date on the potential benefits of healthy individuals taking probiotic supplements to enhance gut health. The review included seven studies, all of which included healthy adults between the ages of 19-88 years old and included anywhere from 21-88 participants. Two studies were from Italy, two from Denmark, one from the United States and one from Germany. Each study ranged in duration from one to two months and compared the effects of probiotics with a placebo, or sugar pill, to measure the effectiveness of the probiotics. Individuals in the studies were not taking any medications. The studies included common probiotic bacteria Lactobacillus, Bifidobacterium, and Bacillus. The probiotics were provided either by biscuit, milk-based drinks, sachets or capsules.


All seven studies collected data by means of assessing gut bacteria using specific molecular techniques, such as stool samples, to determine the effectiveness of probiotics. After carefully reviewing the results of each study, the researchers concluded that overall, there is no convincing evidence for consistent effects of probiotics on microbiota composition in healthy adults.1


We are bombarded with advertisements promoting products that claim to treat every illness, discomfort and undesirable physical attribute you can imagine. We are either consciously or subconsciously pushed to buy products to improve our health and physical appearance – in movies, on TV, in social media, and day to day in the form of billboards, signs and product placement. In a world with a quick cure for any condition, it’s important to review the research before testing out products to avoid wasting money, disappointment and even potentially negative side effects.

Due to the vastly different designs, methods and outcome assessments of each study, the researchers conclude that the absence of evidence is not the absence of any effect of probiotics on digestive health in healthy adults. More research must be undertaken, given the lack of current evidence, to determine if there is any significance supporting healthy adults using probiotic supplements to support a healthy gut microbiota.


If you are interested in using probiotics to treat a diagnosed digestive condition, there is research to support doing so. For example, using probiotics and prebiotics has been demonstrated to effectively help those with celiac disease. Please discuss this matter with your doctor before undergoing any dietary changes or taking probiotic supplements.


1 NB Kristensen et al. Alterations in fecal microbiota composition by probiotic supplementation in healthy adults: a systematic review of randomized controlled trials. Genome Medicine, 8(52): 2016. View

2 Microbiome 101: Understanding Your Gut Microbiota. Prescript-Assist (2016). View

3 The Truth About Probiotics and Your Gut. WebMD (2015). View

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