Photo Credit: by Vitalii Pavlyshynets, Unsplash.com
The Covid pandemic has highlighted the importance of our immune system as part of our overall health. While many Covid infected individuals only developed mild symptoms, others developed more severe complications, with fatal results.
What is the cause of this discrepancy in severity and why are the majority of children not getting as severely ill as adults? My colleagues and I believe the answer lies in the gut microbiome and we highlight this in our scientific publication published in May, 2020.
The Cytokine Storm
A little background on our discovery, which is the first of its kind to link Covid-19 to gut health.
When the covid-19 pandemic first hit the US, New York was affected early. My husband, a Pulmonologist/Intensivist started seeing infected patients in his ICU early on. He found that although many of his sick ICU patients were either elderly or with comorbid conditions, many were younger patients with no medical problems other than an elevated BMI. Many of his ICU patients were also developing a condition called the “Cytokine Storm” and were found to have elevated inflammatory markers in their bloodstream. One of the medications used for treatment focused on inhibiting an inflammatory marker called Interleukin 6 (IL-6). To understand the role of inflammatory markers in the deadly “Cytokine Storm”, we must first understand a little bit about how our immune system responds to infections.
Think of your immune system as the Guardian of the Galaxy—always on the lookout for any intrusions or infections. While the immune system is complex, its ultimate goal is to protect us from anything it perceives as an intrusion. Cytokines act as cellular messengers for our immune system. Interleukins are a smaller subset of cytokines and are secreted in response to a perceived intruder in the body such as a viral infection. There are approximately 18 different types of interleukins and the roles of each varies.
When someone is infected with a virus such as COVID-19, the immune system responds with release of these cytokines, in an effort localize the inflammation caused by the virus. [Source] In some individuals however, the response is more profound than in others and triggers a “Cytokine Storm.” The problem with the Cytokine Storm is that it attracts even more immune cells causing a more systemic inflammation and further damage to tissues.
One of the main pro-inflammatory markers involved in the Cytokine Storm is Interleukin-6 (IL-6). Interleukin-6 is meant to be released in short bursts to localize and control inflammation. Unfortunately, some individuals have persistently elevated levels of IL-6. The prolonged or chronic presence of this pro-inflammatory marker is not good for the body and signals a chronic inflammatory state. Individuals with higher than normal levels of IL-6 at baseline are the same patients that are developing the deadly Cytokine Storm and getting more severely ill from Covid-19. Patients with conditions such as diabetes and heart disease are known to be at increased risk, but why are those with elevated body mass indexes also getting severely ill, and why are the majority of children not? The answer lies in the gut microbiome.
The Role of the Gut
The Gut microbiome of all individuals varies greatly. Children’s guts are overall much healthier than adults and have a higher concentration of certain gut microbes than adults do. Our gut microbes work together with our immune system—a large portion of which is already present in the gut. Children have a much higher concentration of a specific gut bacteria called Bifidobacterium. Bifidobacterium accounts for up to 60-80% of their gut microbiome. The levels start to decrease as we get older and are especially low in those with the same high risk conditions causing severe covid related infections (See figure 1). In our research study, we found that children seem to be protected from more severe Covid infections because Bifidobacterium functions as an immune regulator while down regulating inhibit IL-6—the same pro-inflammatory cytokine that causes havoc in Covid severity and the deadly Cytokine Storm.
Additional Studies linking the gut to Covid
Since our study was first published, several additional studies have been published that show a connection between gut health and Covid. In a January 2021 study out of Hong Kong University, stool samples of patients hospitalized with Covid showed deficiencies of certain bacteria including Bifidobacterium.
Two additional studies published in Italy and Israel also showed that probiotic administration and foods high in live bacteria such as yogurt and kefir, improved the outcome of Covid-19 in infected patients.
What Can you do to improve your gut health?
1- Start by eating the rainbow. Plant based foods such as fruits and vegetables are rich in prebiotic fibers that help good gut microbes such as Bifidobacteria and others thrive in our gut.
2- Incorporate foods such as kefir and yogurt with live cultures, into your diet. Other fermented foods rich in probiotics are apple cider vinegar, kimchi, miso and kombucha.
3- Consider taking a probiotic. Your probiotic should contain Bifidobacterium and Lactobacillus. These are two probiotics that have been shown to be beneficial for overall gut health. If you’d like to start incorporating a probiotic into your daily regimen, here’s a good one to start with it.
Your email address will not be published. Required fields are marked with *.