Immunity has been a hot topic this year, and for good reason. With the COVID-19 pandemic, staying healthy and boosting the immune system has perhaps never been on people's minds more. What’s more, people are coming to realize and believe that building a strong immune system is something that should be prioritized at all times of the year, and not just during a pandemic.
There are many methods and beliefs about strengthening the immune system. Among them is the topic of gut health, and it’s role in immunity. More specifically, the method by which probiotics may help support the immune system has also been highly researched.
This post will address the relationship between our gut health and immune system, and will discuss whether or not probiotics really can make a difference.
The immune system is a complex network of organs, chemicals and cells whose primary function is to prevent and/or treat infection and illness. Under normal circumstances, the immune system can tell the difference between healthy cells and organisms versus those that may be dangerous. When potentially harmful organisms like viruses and bacteria are present, the immune system is designed to respond to help fight off the problem via a variety of mechanisms(1).
About 80 percent of the immune system’s cells are located in the digestive tract, or “gut”(2), which demonstrates its importance in immunity. The gut is an extremely diverse set of organs, composed of many different parts and systems, starting in the stomach and ending in the colon. It houses trillions of bacteria, both beneficial and harmful, which make up a system known as the microbiome (3). The microbiome is unique to each individual, and it plays an extremely important role in many aspects of health, including immunity.
The bacteria in the gut help regulate how efficiently and effectively the immune system works. Under optimal circumstances, a balanced microbiome has bacteria that support the body in a mutually beneficial way. However, when the microbiome becomes imbalanced, meaning the harmful bacteria outweighs the beneficial kind, a condition called “dysbiosis” can occur, which is linked to many health problems.
Many factors can contribute to dysbiosis(4), such as:
Studies show that dysbiosis is associated with many immune-related diseases and is linked to a weakened immune system(5). In addition, other studies show that countries with populations who engage in more factors that lead to dysbiosis (high-sugar diet, high stress and more exposure to toxins) have larger incidences of autoimmune and inflammatory disorders(6). This further demonstrates that an imbalanced gut is closely associated with a weakened immune system.
Patients with respiratory infections (and thus a weakened immune system) generally have gut dysfunction. This implies that the gut-immune relationship can go both ways, with an imbalanced gut both potentially being a cause of illness as well as an effect of it.
With the rising awareness of the relationship between the gut microbiome and immune health, it is understandable to question what can be done about it.
There are many ways to support the balance of the microbiome, some of which include:
Out of all of these possible interventions, probiotics have perhaps been most widely studied for their role in supporting both gastrointestinal health and the immune system. Probiotics are a type of live, beneficial bacteria that primarily reside in the digestive tract. You can read more about their functions and where they are foundhere.
An abundance of research has shown that probiotics play an important part in immunity. Some of the ways they do this is by:
Studies have demonstrated the potential effectiveness of probiotics — specifically oflactobacillus andbifidobacterium strains — on reducing the incidence and duration of viral respiratory illnesses. One particular study on healthy children and adults who developed an acute respiratory infection found that those who received a probiotic intervention had fewer days of illness, fewer illness episodes, and fewer days absent from school, work compared to those who received no probiotics(7).
It is important to keep in mind that the function of probiotics in supporting the immune system extends far beyond respiratory infections. Probiotics have been shown to support overall immune health, including the treatment of allergies and other immune-related disorders(8). Preliminary evidence shows that COVID-19 may be at least partially related to an altered gut microbiota(9).
In fact, China's National Health Commission and National Administration of Traditional Chinese Medicine both recommended that probiotics be used to support and maintain the balance of intestinal bacteria in the treatment of patients with COVID-19 infection(10). However, since there is an abundance of probiotic strains and types, blind use of conventional probiotics is still not recommended for the treatment of COVID-19 until more research and data is completed and obtained(11).
There is much evidence that supports the use of probiotics in supporting the immune system. Probiotics can provide a beneficial impact both on healthy individuals as well as those with an active illness. While probiotics can be obtained from food sources such as fermented foods, the use ofsupplements may provide even greater benefits due to their more targeted approach and significantly larger amounts of bacteria that are more likely to survive in the intestinal tract and do their intended job. As with allsupplements, though, quality is key. Be sure to look for those that contain multiple billions of colony-forming units (CFU’s) and a variety of differentstrains.
Joanna Foley - Contributing Writer, Physician’s Choice