Antibiotics can temporarily wipe out the gut microbiome
DEAR DOCTORS: I got a tick bite, and because there’s Lyme disease in our area, my doctor put me on antibiotics. It prevented Lyme disease, but I’m worried about what it did to my gut microbiome. How long does it take to recover? Can I do anything to help?
DEAR READER:
Over the past few decades, we have become increasingly aware of how the trillions of microbes that live in the human gut support our physical and mental health. These diverse colonies of microorganisms play key roles in physiology, nutrition, digestion, metabolism, immune function, hormone balance, neural activity and disease prevention. This has led to much speculation about what happens to the gut microbiome when antibiotics are needed to control a bacterial infection.
Two things turn out to be true. One is that antibiotics save millions of lives each year. The other is that using them disrupts the complex ecosystems of the gut microbiome. This means not just a decrease in the numbers of microorganisms in the large intestine, but also a decline in their diversity.
The good news is that researchers have found the gut microbiome is resilient and, over the course of several months, will gradually recover. The speed and scope of that recovery is affected by several factors. The type of antibiotic used and how frequently they play a role. Eating a fiber-deficient diet prior to antibiotic treatment also leads to a slower recovery. Older adults, infants and young children may also see a delayed return of their gut flora.
You can support the recovery of your gut microbiome in several ways. Although logic suggests taking probiotics, researchers have found this can actually delay recovery. It has been found that following a course of antibiotics, the limited numbers of bacteria in probiotic products can colonize the gut. This markedly slows the balanced return of the diverse and complex colonies of microbes that are unique to each person’s microbiome.
A more effective approach is to feed your gut — literally. Concentrate on a wide and varied range of prebiotic foods. These include the fresh vegetables, leafy greens, legumes, nuts and fruit that contain the fiber and micronutrients our gut flora thrive on. Include plenty of fermented foods, as well, such as yogurt, kefir, kombucha, pickles, miso and sauerkraut. Be sure to choose products with live cultures.
Physical activity has been shown to greatly improve gut health. Choose a wellrounded program of aerobic activity to get
your heart pumping, strength training to build muscle strength, and activities to enhance and preserve flexibility and agility.
Studies show environmental factors also play a significant role in healing an injured gut. This includes being around and interacting with animals, gardening, and spending time outdoors and in nature. These expose you to a wide array of the “good” microbes that help boost gut diversity. So does being among other people who share their microbes with every breath, kiss, hug and handshake.
There are no shortcuts to good gut health. Eat well, take care of yourself and be patient. Your gut will thank you.
Eve Glazier, M.D., MBA, is an internist and associate professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and assistant professor of medicine at UCLA Health.
Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.