Long journeys to outer space can be very hard on the human body, impacting metabolism, immunity, and mental health. These issues must be considered before we can send humans back to the Moon or to Mars.
In the new paper, the experts report that promoting a healthy gut microbiome could prevent the harmful side effects of space travel. They will now attempt to identify the specific microbes that can provide the most benefit.
The microgravity environment can result in muscle breakdown, reduced bone mass, nausea, and can disrupt the gut microbiome, explained the researchers. These factors contribute to even bigger problems like malnourishment, gastrointestinal infection, and inflammation. Astronauts may also experience metabolic disturbances, such as decreased sensitivity to insulin and cognitive decline.
Professor Silvia Turroni of the University of Bologna and Professor Martina Heer of the University of Bonn reviewed a collection of studies that focus on gut microbes and space-related health. Many of these studies suggest that disruptions in the gut microbiome occur during space travel.
In particular, one study found that the microbiomes of astronauts became more similar to each other while they were on the same space mission. There was also an increase in bacteria associated with intestinal inflammation and a decrease in those with anti-inflammatory properties.
“Changes in the microbiome are likely to lead to the breakdown of the balanced and complex relationship between microbes and their human host, with potentially severe repercussions on the functionality of body systems,” said Professor Turroni.
However, the researchers found evidence that manipulating the gut microbiome may be an effective strategy to maintain good health on a long journey into space.
“The literature suggests that nutritional countermeasures based on prebiotics and probiotics hold great promise to protect space travelers,” said Professor Turroni.
Microbial treatments may be as simple as nutritionally balanced meals with lots of fiber to kickstart metabolism. They could also be more targeted, such as probiotics or other microbial supplements to boost immunity.
“The well-being of the gut microbiome of space travelers should be among the primary goals of long-duration exploratory missions,” said Professor Heer. “To ensure the success of the mission, we must not overlook the myriad of microorganisms that reside in our gastrointestinal tract and make sure they are in balance.”
While missions to Mars will look for evidence of microbial life on the red planet, the researchers believe that it will be microbes here on Earth that make it possible for us to get there in the first place.
The study is published in the journal Frontiers in Physiology