Probiotics For Healthy Adults: Help or Hype

Does everyone need to take a probiotic?


By Ross Pelton, RPh, PhD, CCN

It is now indisputable that a healthy microbiome is critical for good health. Many studies have reported that probiotic supplements are beneficial in the treatment of gastrointestinal disorders such as colitis, diarrhea, Crohn’s disease and IBS.i Also, an increasing number of scientific studies are reporting that probiotic supplementation can provide benefits for conditions outside the GI tract such as oral health, respiratory infections, eczema, bladder and vaginal infections, and psychiatric disorders like anxiety, depression, and schizophrenia.ii iii iv However, there has been some controversy about whether probiotic supplementation in “healthy adults” is helpful or hype.

In a study titled “A review of probiotic supplementation in healthy adults: helpful or hype?” the authors reviewed 45 clinical trials on the use of probiotics in healthy adults published between 1990 and 2017v. The authors reported that the studies reviewed could be classified into five major areas of benefit. The studies examined addressed the following areas of concern: changes in the microbiome (15 studies), immune system response (16 studies), and blood lipids and/or lowering of cardiovascular risks (14 reviews), gastrointestinal discomfort (11 studies) and female reproductive health (4 studies).

The overall results indicated that probiotic supplementation in healthy adults could lead to a short-term increase in the concentration of the strains of bacteria supplied in the probiotic supplements. The evidence also indicated that probiotics could be helpful in improving immune system responses, stool consistency, bowel movement, and vaginal lactobacilli concentration. There was insufficient evidence to support the role of probiotics to improve blood lipid profiles.

In their conclusion, the authors stated that the results of studies on the use of probiotics in healthy adults over the past 27 years indicate that probiotic consumption can provide useful improvements in the immune, gastrointestinal, and female reproductive health systems in healthy adults.

My Analysis and Comments:

There are two critical points that I want to address related to this study and its reported results.

1) Health is a continuum: Remember, health is not merely the absence of disease. In most people, even healthy people, there is generally room for improvement in one or several areas of health. In this review of studies on the use of probiotics in healthy individuals, it was shown that probiotic supplementation could result in improvements in GI health, immune system function and female reproductive system. So, probiotics can make healthy people healthier

2) Probiotic Benefits are Short-Lived: It was exciting and important to note that the health benefits people gained from taking probiotics were transient or of short duration. This is because the strains of bacteria in probiotic supplements are generally not the same strains that individuals harbor in their innate microbiome. The bacteria in probiotic supplements can provide health benefits for individuals for approximately 7-10 days as they are passing through the intestinal tract. Because the strains of bacteria in probiotic supplements are generally not the same as the individual’s natural bacteria, the supplemented strains do not adequately adhere to the intestinal mucosal cells and colonize. In fact, in a study titled Beneficial Properties of Probiotics, the authors stated the following:

“Continuous intake of orally administered probiotics is necessary because permanent colonization of probiotics is uncommon.” vi

Conclusion: Probiotic supplementation can provide benefits to Individuals with health problems AND to healthy adults. However, the benefits from probiotic supplementation are generally believed to be of short duration because the ingested bacteria are not the host’s natural bacteria. This means the bacteria in probiotic supplements are not likely to colonize and remain resident for extended periods of time.

Therefore, the bottom line is that yes, probiotic supplements can provide health benefits, but they must be ingested continually to continue receiving their health-promoting benefits.

Since a healthy microbiome is now recognized to be one of the most critical aspects of health, we need to educate people about the importance of taking a premium probiotic such as Dr. Ohhira’s Probiotics on a daily basis to help maintain a healthy microbiome


i Verna EC and Lucak S. Use of probiotics in gastrointestinal disorders: what to recommend? Therapy Adv. Gastroenterology. 2010 Sep;3(5): 307-319.
ii Reid G. (2012). Extra Intestinal Effects of Prebiotics and Probiotics. GR Gibson and RA Rastall (Ed.), Prebiotics: Development & Application. New York; John Wiley & Sons, Ltd.
iii Foster JA and McVey Neufeld KA. Cut-brain Axis: how the microbiome influences anxiety and depression. Trends in Neurosciences. 2013 May;36(5):305-312.
iv Severance EG, et al. Probiotic normalization of Candida albicans in schizophrenia: A randomized, placebo-controlled, longitudinal pilot study. Brain Behav Immu. 2017 May;62:41-45.
v Khalesi S, et al. A review of probiotic supplementation in healthy adults: helpful or hype? European J Clin Nutr. March 26, 2018;
vi Shi LH, et al. Beneficial Properties of Probiotics. Trop Life Sci Res. 2016 Aug;27(2):73-90.