Probiotics boost athletes’ immune system defenses: Study

Athletes given a placebo were 2.2 times more likely to experience one or more symptoms of respiratory infection compared to those given probiotics. ©iStock

Taking daily probiotics may help boost immune systems of training athletes and reduce their risk of upper respiratory tract infections (URTI), a study has found.

The small-scale study looked at the impact of a daily dose of a multi-species probiotic on various markers of immune system function as well as symptoms of URTI and athlete performance compared to a placebo.

The probiotic contained 1 × 1010 colony forming units (CFU) of the species Bifidobacterium bifidumBifidobacterium lactisEnterococcus faeciumLactobacillus acidophilusLactobacillus brevis and Lactococcus lactis.  

Comparing the 33 athletes, they found after 12 weeks of intense excersise the placebo group had 11% lower post-exercise levels of the amino acid tryptophan, which plays a role in the control of immune responses, compared to before the experiment began.

However for the probiotic group this was unchanged, according to the results published in the journal Nutrients.

The placebo athletes were also 2.2 times more likely to experience one or more URTI symptoms compared to those on probiotics.

However the probiotics did not benefit athletic performance.

Winning races, losing immunity 

Training schedules, poor nutrition, lack of sleep, stress and consequently impacted immune systems are all factors meaning athletes are more susceptible to URTIs.  

“Numerous studies have shown that prolonged intense physical exercise is associated with a transient depression of immune function in athletes. While moderate exercise beneficially influences the immune system, a heavy schedule of training and competition can lead to immune impairment associated with an increased risk of upper respiratory tract infections (URTIs) due to altered immune function,” said the researchers from the Medical University of Innsbruck in Austria. 

“It has been suggested that exhaustive exercise creates a potential ‘open window’ of decreased host protection, during which viruses and bacteria can gain a foothold, increasing the risk of developing an infection.” 

It’s been estimated that during major competitions lasting 2–3 weeks, about 7% of athletes typically experience at least one episode of illness and about half of these are respiratory related.

Next race

The researchers said that while the effects seen in their study appeared to be connected with changes in tryptophan metabolism, the findings were only preliminary and further investigation into the precise mechanisms was needed.

“In addition, more research is required to clarify issues of strains, dose–response, mechanisms and best practice models for probiotic implementation in various sports disciplines,” they said.  

“It should be further investigated as to whether regular exercise per se affects human microbiota characteristics, for how long and how much exercise is needed.”

The results follow a single-strain study published this year that suggested Lallemand’s Lactobacillus helveticus may reduce the duration of URTIs in athletes.

The infection lasted an average of 4.7 days for the athletes given probiotics compared with 7.25 days in the placebo group.

Yet this too was a small-scale study with 39 participants, and its authors echoed calls for larger scale tests.


Source: Nutrients   

8(11), 752; doi:10.3390/nu8110752

“Probiotic Supplements Beneficially Affect Tryptophan–Kynurenine Metabolism and Reduce the Incidence of Upper Respiratory Tract Infections in Trained Athletes: A Randomized, Double-Blinded, Placebo-Controlled Trial”

Authors: B. Strasser, D. Geiger, M. Schauer, J. M. Gostner, H. Gatterer, M. Burtscher and D. Fuchs


Probiota 2017

Prebiotics and probiotics and the microbiome will be discussed in-depth at Probiota 2017 in Berlin on February 1-3.

From microbiome advances to start-up game changers to market stats that matter and crucial formulation and regulatory knowledge, this is a congressional must-have. Will you be joining your peers in one of Europe’s great cities?

Click here for more.

Related News

© iStock / xomato

Probiotic-prebiotic-antioxidant combination shows benefits for triathletes: Study


Multi-strain probiotic could aid gut health – even if you’re healthy

© iStock/shironosov

Probiotic may reduce the risk of common cold: Yakult study

The guts for sports success: Microbiome study highlights differences in elite athletes

The guts for sports success: Microbiome study highlights differences in elite athletes

© iStock / Jacob Ammentorp Lund

Lafti L10 probiotic shows respiratory benefits for athletes: RCT

© iStock

Probiotics may reduce post-exercise inflammation, offer performance benefits: RCT

RCT findings back probiotic strain to shorten duration of cold and flu: Chr Hansen study

RCT findings back probiotic strain to shorten duration of cold and flu: Chr Hansen study

Map My Gut offers paying customers specialist gut microbiome analysis and personalised nutrition advice based on metagenome testing. ©iStock/TLFurrer

'In five years this will be routine': Map My Gut start-up offers personalised microbiome advice

Probiotics protection: Yeast wall compound improves survival in food products

Probiotics protection: Yeast wall compound improves survival in food products


Top prebiotic & probiotic NPD trends

The bacteria most frequently exploited as probiotics are the Gram-positive Bifidobacterium and Lactobacillus families. ©iStock

Directing psychobiotic ‘talk’ via gut-brain network key to neurological benefits: Study

Getting a probiotic health claim approved has been 'rendered impossible', says IPA Europe. ©iStock/goolyash

Is it time to admit it's impossible to get a probiotic health claim?

Related Products

See more related products

Submit a comment

Your comment has been saved

Post a comment

Please note that any information that you supply is protected by our Privacy and Cookie Policy. Access to all documents and request for further information are available to all users at no costs, In order to provide you with this free service, William Reed Business Media SAS does share your information with companies that have content on this site. When you access a document or request further information from this site, your information maybe shared with the owners of that document or information.