By analysing the gut microbiota of elite athletes, scientists are discovering new ways to help improve our performance and ward off illness, says Peta Bee

HOW healthy is your gut? Is it primed with beneficial bacteria that will help you to ward off illness, allergies and weight gain, or is the balance of bugs in your digestive system off kilter?

Science has proven that the status of our microbiota, the ecosystem of not only bacteria, but yeasts, fungi and viruses, influences everything from inflammation to metabolism and our susceptibility to disease. Now scientists think that the best bugs are found in most athletic of our species — elite sports people — who might hold the key to explaining how we can all bulletproof our guts to their super-human standards.

Emerging studies suggest that the bacteria found in the guts of top athletes is in many ways superior to the average microbiota. Higher levels of bacteria that speed up recovery following a workout and convert nutrients to energy more efficiently have been found in the digestive systems of the fastest and strongest human beings on the planet.

Now, the world’s leading microbiologists think that if they can harvest the bugs from elite athletes’ guts and give a dose to the more sedentary members of society, they would benefit in terms of improved health and fitness.

Spearheading this cutting-edge area of research is a team from the APC Microbiome Institute at the University College of Cork. Led by Professor Fergus Shanahan, the Institute’s director, they have conducted trials on top rugby players that found that the sports people had a much greater diversity of gut bacteria than controls.

“We studied both the composition and the functionality of the microbiome of the athletes,”Shanahan says. “And it showed that their microbiota had evidence of upregulated pathways that meant they were better able to extract and use energy and nutrients from their diet.”

Athletes in their trial also had higher levels of Akkermansia bugs, associated with leanness, than overweight subjects. “This was the most noteworthy discovery because the Akkermansia organisms are associated with better health and less metabolic and cardiovascular disease,” Shanahan says.

“Overall, the athletes we studied had a much greater diversity of gut bacteria which is what is needed to achieve peak fitness and health.”

We each have a microbiome that is unique, determined largely by our genes but influenced by our lifestyles. Stress, a lack of sleep, poor dietary choices and illness or medication can upset the delicate balance of our gut.

“Our microbiome profile is shaped by almost every aspect of life from the mode of delivery at our birth — whether we are born via caesarian section, for instance — and whether we are breast-fed, to our daily habits as we grow up” says Orla O’Sullivan, a researcher in the APC Institute. “Antibiotics and other medications can have a negative impact which is why a course of probiotics is a good idea after a course of medication.”

Exercise appears to play a role in promoting gut health, but we don’t yet know to what extent. “We showed that exercise or physical fitness was associated with a more diversified and healthy microbiota, but we have not yet shown a cause-effect relationship,” says Shanahan.

It could be, he says, top athletes’ meticulous approach to their diet has a greater influence of gut bacteria than their training. And too much exercise might have a negative effect microbial composition.

“It might be that there are adverse changes to the microbiome when athletes overtrain,” he says. “That is something we are looking at now.”

Elsewhere, a team from Harvard University has tapped into the microbiome of top runners and rowers to determine which specific bacteria might underpin their ability to push their bodies faster and further than other people.

“We’re mining the biology of the fittest and healthiest people in the world,” says Dr Jonathan Scheiman, a researcher in the Church Laboratory in Harvard Medical School’s department of genetics and a member of the research team. “We’re then extracting and that information and hope to use it to help other athletes, but also to enable everyday exercisers to become fitter.”

As part of their research, they have sequenced the athletes’ microbiome, observing how it changes when they are training competing or recovering. In one trial involving 20 elite marathon runners, they found that levels of bacteria known to play a crucial role in the breakdown of waste products like lactic acid soared after the race, significantly more so than in a control group of healthy non-runners. By giving this bacteria to slower runners, it might improve their ability to keep going for longer.

Is it realistic that we might soon be able to pop a pill containing the bacteria of Olympians? Researchers think so. “I think in the immediate future harnessing novel probiotics from athletes is the next step,” O’Sullivan says.

Scheiman and his colleagues at Harvard have already created a spin-off company called Fitbiomics and plan to launch a supplement to market within the next 12 months. What, though, can we do to bulletproof our microbiome in the meantime?

“Fundamentally, in order to maintain good gut health, the best recommendation is to consume healthy, diverse diet,” O’Sullivan says. “And while we have yet to determine if exercise truly modifies the microbiome, it can never be a bad thing to be more active.”