New research suggests they have a more lasting impact on our bodies than previously thought, according to HealthDay News.
A study of nearly 15,000 adults found that some antibiotics can alter the community of beneficial bacteria in our digestive systems for almost a decade.
The study, conducted by a team at Uppsala University in Sweden, mapped the gut microbiome of nearly 15,000 adults in Sweden.
Each participant’s stool sample was analyzed, and participants answered a detailed questionnaire about their lifestyle and diet.
Then, using national drug registries, the scientists were able to see exactly which medications people had taken years earlier. They adjusted for the effects of antibiotic use, other medications taken, and several characteristics known to affect the microbiome.
The results were surprising. For some antibiotics, even a single course of use was associated with a reduction in bacterial diversity four to eight years later.
Overall, the worst effects were seen in the first year after antibiotic use.
“We can see that antibiotic use four to eight years ago is associated with the composition of a person’s gut microbiome now,” said Gabriele Baldanzi, the paper’s first author and a research assistant at Uppsala University. “Even a single course of treatment with certain types of antibiotics leaves an imprint.”
This is significant because a healthy, diverse microbiome supports human health and well-being. It acts as a shield against infections, boosts immune health and helps the body digest food for energy.
The study showed that not all antibiotics were created equal.
The damage seen in the gut depended on the type of antibiotic used. Clindamycin, fluoroquinolones, and flucloxacillin had the most lasting negative effects on gut health.
On the other hand, penicillin V and some of the broad-spectrum penicillins, the most commonly prescribed antibiotics, were much more friendly to the gut. Their effects were minimal and wore off relatively quickly.
The balance of gut bacteria is important for human health.
The researchers noted that previous research has linked high antibiotic use to an increased risk of type 2 diabetes, heart disease, obesity, serious gastrointestinal infections, and even colon cancer. Scientists suspect that these long-term microbiome changes may be the reason.
“Our study findings may help inform future recommendations on antibiotic use, especially when choosing between two equally effective antibiotics, one of which has a weaker effect on the gut microbiome,” said Dr. Tove Fall, senior researcher and professor of molecular epidemiology at Uppsala.
Despite the findings, the researchers urge patients not to stop taking the medications prescribed by their doctors. Instead, the goal is to encourage appropriate medication when necessary to protect the body’s internal ecosystem in the long term.