Probiotics: Good for More than Our Guts

Most people are aware of the digestive benefits of probiotics, but research now suggests that probiotics may also stimulate the immune system during times of stress, improve our mood, and decrease the amount of time that flu symptoms are experienced. Probiotics are live microorganisms (or ‘good bugs’) that, when administered in adequate amounts, offer health benefits to the host. More and more health care practitioners are beginning to recommend probiotics; they are often touted as a staple supplement due to their ability to balance the microbiome (the population of trillions of bacteria within our bodies).

One of the best ways to positively influence declining immune health that is due to stress is with the use of probiotics. Stress has a significant influence on the amount of ‘good bugs’ there are in our system relative to the number of ‘bad bugs’. In chronically stressed individuals, bad bacteria (like Enterobacteria and E. coli) tend to increase in number, while good bacteria like Bifidobacteria and Lactobacilli decrease. Probiotics can help restore the Bifidobacteria and Lactobacilli populations, thus having a positive effect on the immune cells within the gut and the immune system as a whole.

Another way probiotics positively influence our health is through their impact on our mood. There is now evidence that shows gut health to be inextricably linked to brain health. This is called the gut-brain axis and it encompasses bidirectional communication between the gut microbiome and the brain. Altered microbiota, for example, has been linked to depression, anxiety, and autism spectrum disorder. The good news is that when probiotics are introduced to the system they are able to modulate the severity of these mood disorders. Probiotics have also been shown to increase brain activity and improve mood even in healthy individuals.

Trials have also been conducted that assess the effectiveness and safety of probiotics when used to prevent and modulate acute upper respiratory tract infections. At this time, the research is very positive – the use of probiotics for respiratory infections shows beneficial results. Probiotics not only reduce the incidence of an acute infection, but also the duration and severity of an acute upper respiratory tract infection.

As more research becomes available, the consensus is that the gut microbiome appears to have an influence on nearly all systems and levels of the human body. Supplementing with probiotics is a one way to replenish, rebuild, and maintain the gut microbiota. Talk to your naturopathic physician about the specific strains and dosing that would work for your needs.


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Manuel PM, et al. Oral probiotics supplementation can stimulate the immune system in a stress process. Journal of Nutrition and Intermediary Metabolism. 8:29-40. 2017.

Quick M. Cochrane Commentary: Probiotics For Prevention of Acute Upper Respiratory Infection. EXPLORE: The Journal of Science and Healing. 11(5):418-420. 2015

Zhou L, Foster JA. Psychobiotics and the gut-brain axis: in the pursuit of happiness. Neuropsychiatric Disease and Treatment. 11:715-723. 2015.