The human body is a uniquely connected system with vast communication networks that operate with the ultimate goal of systemic balance, also known as homeostasis. One of our primary communication stations is our gastrointestinal system, specifically our microbiome. This system interacts with our entire body both directly and indirectly. While we always associate gut issues such as gas, bloating, diarrhea, and constipation with our gut, we often do not connect other non-gut symptoms with the intestinal tract. However, the literature continually demonstrates how the many different organ systems interface with our gut, our lungs being one of them!
Our respiratory tree actually has its own microbiome, which closely resembles the bacteria makeup of our gut. The gut-lung axis is a communication channel between our gut and our lungs. What's happening in the gut can affect the lungs and vice versa. Studies demonstrate how a Salmonella infection in the lung will cause a Salmonella-specific immune response in the gut. We also see that consumption of fiber-rich foods produces short-chain fatty acids in the gut, which act on the lungs to reduce inflammation and allergic responses. Researchers suggest that one of the main routes this connection occurs is through our lymphatic system- a highly specialized group of immune cells laced throughout our entire body.
Antibiotics and Lung Disease
The simplest demonstration of our gut-lung axis is found through the use of antibiotics. Oral antibiotics are commonly prescribed for bacterial infections of our respiratory tree. Typically, a patient takes an oral capsule or liquid antibiotic, which is absorbed via the gut and dispersed to the entire system, including our lungs, providing antibacterial effects. Antibiotics are undeniably one of the greatest advents of modern medicine. Since their discovery, millions of lives have been saved. Currently, however, antibiotic overuse is described as a global public health challenge.
Research reveals that antibiotics are not always necessary for upper respiratory infections because many of these infections are caused by viruses, not bacteria. We also know that most upper respiratory infections are self-limited, meaning they go away on their own. When there is an actual bacterial-not viral infection of the respiratory tree, antibiotics are a simple, cheap, and effective treatment. In some chronic lung disease states, such as cystic fibrosis, antibiotics can become a mainstay of therapy due to the occurrence of pulmonary infections. While antibiotics play an important role in protecting the lungs from bacterial infections, they can also negatively affect them.
Antibiotics and Our Gut
Our lung health is undeniably linked with our gut health. Antibiotics can be detrimental to our gut health, especially with chronic use. Simply put, antibiotics induce gut dysbiosis. Dysbiosis refers to the imbalance of microbial families in the gut. We all have many different types of bacteria, fungi, and other microbes present in our gut. The relative balance and ratios of these microbes create a healthy gut environment. When one microbial family is overgrown relative to the others, it creates a state of dysbiosis, which is associated with many chronic diseases, including lung disease.
One murine model studying the use of antibiotics on lung infections found that the use of gut-specific antibiotics leads to a reduced lung immune cell response. The alteration in microbial populations of the gut secondary to antibiotic use has also been shown to alter the immune response in a way that may actually drive the development of allergic lung diseases like asthma and allergies. Other studies demonstrate the potentially disruptive role of antibiotics on the gut-lung axis. While they can be life-saving drugs, antibiotics can also pose risks of adverse effects and induce gut dysbiosis leading to gut-lung axis disruption and other systemic consequences.
So, you may be asking yourself, "what exactly can I do to protect myself from the unwanted side effects?" Here are a few simple steps you can take:
If you're prescribed an antibiotic for an upper respiratory infection, discuss the possibility of viral versus bacterial and the necessity for the antibiotic with your physician.
Support your gut-lung axis by consuming a fiber-rich diet which can help to produce anti-inflammatory short-chain fatty acids.
Consider a probiotic that supports the microbiome and, secondarily, the lungs. There are specific strains that have been shown to have lung health benefits. As always, discuss with your doctor before you change your health regimen.
About the Author
Asia Muhammad, ND, is a Doctor of Naturopathic Medicine and an expert in functional medicine and personalized health. She specializes in gastroenterology, mind-body medicine, and stress management and has received additional training in mind-body therapies. Learn more at asiamuhammad.com or follow Dr. Asia on Instagram.