An unhealthy gut can reduce the chance of surviving a COVID infection.
Factors like a “Western diet”, long-term illness, and aging can cause microbial imbalance in the gut, resulting in a leaky gut.
Leaky gut syndrome enables the COVID-19 virus to get through the surface of internal organs and the digestive tract, making the infection worse, a study has found.
The severity of infection is due to the ACE2 protein which is the entry point for SARS-CoV-2.
The protein is largely located on the surface of organs such as intestines, heart, and lungs.
SARS-CoV-2 infection can cause severe symptoms such as respiratory complications and high fevers.
Furthermore, autopsies show that the infection can damage the heart, liver, gastrointestinal (GI) tract, spleen, and kidneys.
Some hospitalized patients not only have breathing difficulty but also experience nausea, vomiting, and diarrhoea.
This suggests that if the virus reaches the GI tract, it can cause more damage to patients.
We now know that older people and those with health conditions such as diabetes, obesity or even high blood pressure are at increased risk of severe coronavirus disease.
It appears that aging and underlying health conditions can disturb gut microbiota, causing gut barrier dysfunction in which the wall of the intestine becomes permeable.
In this situation, toxins and pathogens including any virus or bacteria can easily enter the lining of the intestine.
Dr Heenam Stanley Kim, the study’s author, said:
“There seems to be a clear connection between the altered gut microbiome and severe COVID-19.”
Some studies have argued that unhealthy gut microbiomes could be the hidden cause of severe infections in some people, Dr Kim noted.
For instance, a study in Singapore found that 50 percent of symptomatic patients with COVID-19 carried a noticeable amount of the coronavirus in stool samples, while only half of them had gastrointestinal symptoms, suggesting the possibility of no harm by the virus despite reaching the GI tract.
Dr Kim, however, hinted that whether the symptoms progress is dependent on people’s gut health when infected.
Several studies have found that COVID-19 patients have a lower level of bacterial diversity and beneficial bacteria but higher amounts of pathogenic organisms.
The microbial imbalance (gut dysbiosis) have also been found in influenza patients.
The coronavirus appears to reduce a type of bacteria that produces a short-chain fatty acid called butyrate.
This fatty acid is important for gut health since it enhances intestinal barrier function.
Zuo and colleagues suggest the use of a probiotic formula addressing gut dysbiosis in order to enhance immune defence against viral infections such as COVID-19.
The other issue is that the Western diet causes changes in gut microbiome composition.
Dr Kim noted that Western Europe and the United States are well known to be wealthy with a well-functioning health care system, but they are one of the worst hit by the coronavirus pandemic.
These countries have one thing in common; the Western diet, which is poor in fibre.
Dr Kim said:
“A fiber-deficient diet is one of the main causes of altered gut microbiomes.
And such gut microbiome dysbiosis leads to chronic diseases.”
Eating fibre rich foods can lower the severity of illness but patients with severe Covid-19 might need fecal microbiota transplantation to treat the infection.
Dr Kim said:
“The whole world is suffering from this COVID-19 pandemic, but what people do not realize is that the pandemic of damaged gut microbiomes is far more serious now.”
The study was published in the journal mBio (Kim, 2021).