VANCOUVER, British Columbia — Fasting may be the most effective way to overcome serious bacterial illnesses, like salmonella, a new study reveals. Scientists from the University of British Columbia say fasting changes the body’s gut microbiome, making it more able to protect against full-on infections.
In experiments with mice, researchers restricted food for 48 hours before and during a case of food poisoning using the bacteria Salmonella enterica serovar Typhimurium. This strain of germs is a common source of foodborne illnesses in people.
Until now, it’s been unclear whether avoiding food protects a patient from bacterial infection or increases their vulnerability to food poisoning. The new study finds fasting actually decreased the signs of bacterial infection in comparison to mice who continued to eat while sick. Moreover, fasting eliminated almost all of the tissue damage and inflammation in the mice’s intestines.
‘Fasting or calorie restriction has potential to beneficially modulate GI diseases’
When researchers fed fasting mice a day after their experiment, they discovered a dramatic spike in Salmonella bacteria invading the intestinal walls. However, the team did note that inflammation was still under control thanks to the previous day’s fast.
Study authors also report that the results did not hold true when they introduced Salmonella to the mice’s bodies intravenously. Additionally, fasting did not full protect germ-free mice from Salmonella contamination; these are mice which lack a normal gut microbiome. The team says these findings suggest that fasting directly affects the makeup of healthy bacteria in the gut, helping the body to fight off invading germs people ingest.
Scientists discovered the same results when they switched from Salmonella to another bacteria, called Campylobacter jejuni.
“These data suggest that therapeutic fasting or calorie restriction has the potential to beneficially modulate infectious and potentially non-infectious gastrointestinal diseases,” the researchers write in a media release.
“Our research highlights the important role that food plays in regulating interactions between the host, enteric pathogens and the gut microbiome. When food is limited, the microbiome appears to sequester the nutrients that remain, preventing pathogens from acquiring the energy they need to infect the host. While more research is needed, fasting or otherwise adjusting food intake could be exploited therapeutically to modulate infectious diseases in the future.”
The study appears in the journal PLOS Pathogens.