What Happens to Your Gut When You Take Antibiotics, According to a Gastroenterologist
Gut health has been a focus in the nutrition space for quite some time. Including gut-healthy foods and drinks into your diet is a great way to fuel your body with nutrients that promote healthy digestion.
But there may be a factor in your routine that you didn't realize is causing a harmful punch to the gut.
Gastroenterologist and cookbook author Will Bulsiewicz, M.D., recently talked about antibiotics' impact on the gut microbiome on the podcast The Proof with Simon Hill. On the show, the pair discussed understanding antibiotics and their effect on the gut. Here's what the doctor had to say about the correlation.
"There are three main things that happen within the microbiome when you take antibiotics," Bulsiewicz explained. "One, a loss of diversity. Two, you are causing widespread damage to the species. And three, you are choosing and selecting the resistance microbes."
A healthy gut means a diverse microbiome, but antibiotics, in addition to killing "bad" bacteria, also wipe out "good" bacteria. Taking antibiotics when not needed also promotes antibiotic resistance, causing the germs to develop a tolerance for the drugs designed to kill them, per the Centers for Disease Control and Prevention.
Bulsiewicz suggests that taking long-term antibiotics can cause "medically induced dysbiosis." Dysbiosis is a disruption to the gut microbiome which causes an imbalance within its microorganisms. Symptoms of the illness include digestive problems, inflammation and chronic fatigue.
Bulsiewicz makes the connection between dysbiosis and long-term antibiotics based on a 2018 study published in Cell, which explains how the gut is impaired after antibiotics:
"They took a group of 20 people, and let me say, these people did not have infections. And the reason why they chose healthy people is because if a person has an infection, their microbiome is already disrupted, so let's start with a healthy microbiome that has not been disrupted and see what the effects of these antibiotics are."
Four different types of antibiotics were given to the studied group, and while the response to the common drug is individualized and dependent on the person, there was a frequent result. Some participants in the study experienced negative symptoms to the gut microbiome, including serious infection in the colon.
"The people that are most at risk are people with inflammatory bowel disease," Bulsiewicz cautioned. "I think there's a vulnerability there where if you already have a damaged dysbiotic gut then there is a higher risk of having complications as a result of your antibiotics."
The Bottom Line
If you are prescribed antibiotics for treatment, continue taking them as directed by your medical provider. Bulsiewicz agrees that antibiotics are helpful and needed when treating an infection. However, antibiotic overuse is common, with the CDC estimating that 1 in 3 antibiotic prescriptions are unnecessary. Many of these unnecessary prescriptions are prescribed to treat viruses, like the common cold or the flu, which do not respond to antibiotics. Though antibiotics play an important role in treating infections, they are not a cure-all for every illness. It's important to work with your medical provider to determine if an antibiotic will help your ailment before requesting a prescription. If you believe that long-term antibiotics are causing problems with digestion and your gut health, talk to your doctor about your concerns. Check out these 12 foods to improve your gut health overnight.