improve your microbiome and cut the risk of severe COVID 

How to improve your microbiome and cut the risk of severe COVID 


One of the biggest “new things” in medical research over the past decade has been an understanding of the far-reaching importance of the human microbiome—the trillions of bacteria, viruses, and fungi that inhabit our skin and our insides, and necessary for good health. One important function of the microbiome is to keep our immune system functioning well. 

Recent studies are showing that people with a healthier microbiome are more resistant to suffering severe COVID symptoms. Our immune system is of special importance during this pandemic, and in this post, we will give you some quick ways to improve your microbiome, based on new research published in Nature Medicine, in January 2021.

Cytokine storm

What is lethal for many people with severe COVID is not the infection itself, but the body’s reaction to the virus. In some people, rather than mount an appropriate immune response, their body launches what we might call a “nuclear” response—an overly exaggerated response with a huge release of inflammatory cytokines. This avalanche of cytokines end up attacking not only the virus, but various organs in the body as well, such as the lungs, kidneys, heart, and brain, and may lead to septic shock, and unfortunately, death. 

Gut microbiome and COVID

Researchers are trying to determine why some people’s immune system launches this inappropriate “nuclear” response, and one of the theories is that it might be, at least in some, an imbalance in the microbiome inside their intestines. An early study to test this theory was carried out at the Chinese University of Hong Kong, with results just published in the British Medical Journal Gut on 11 January, 2021.

The researchers studied stool samples of 100 people with various severities of COVID infection, and 78 uninfected people. They found that indeed, there was a strong correlation between abnormal bacteria in the gut and severity of COVID infection. They also found that the people who cleared the virus out of their system—but continued for months to have low-grade COVID symptoms (such as breathing problems and fatigue)—were also more likely to have a disordered gut microbiome. 

This was an “observational” study and does not prove that an imbalanced microbiome makes some people more prone to severe COVID and more likely to have long-term symptoms (“long-haulers”), but the study findings fit with what is known about the gut microbiome and the immune system. The lesson is—especially during the pandemic, we should do what we can to promote a healthy microbiome in our own gut!

How to improve your gut microbiome

Extensive research just published in Nature Communication concluded that what we eat is the main determinant of the health of our gut microbiome. The authors recommended:

  1. Eat less processed food, which contains added sugars, salt, and other additives. For example, instead of processed potato chips, eat homemade popcorn as a snack, which is much healthier. Instead of sugary or artificially sweetened juice or soda, drink water, lime juice, or tea. 
  1. Eat more unprocessed foods, especially vegetables, nuts, eggs, and seafood. 
  1. Eat foods with lots of fiber. Fiber is the “macronutrient” that feeds the good bacteria in your gut. For example, instead of white bread, choose the whole wheat option!

For more details about how to improve your internal microbiome, read this post from 2018:

How to improve your internal microbiome

Finally, here is a publication from the Brazilian Health Ministry and the University of São Paulo which we highly recommend. It is richly illustrated, and while very detailed, is the best quality publication we have seen come from the Brazilian government directed to the general population!

Dietary Guidelines for the Brazilian Population

This publication was so excellent that it was successfully released in English and Spanish as well, and has received international praise. 

To find a doctor, of any specialty, anywhere in Brazil, check out our website:

Esta postagem também está disponível em: Portuguese (Brazil)

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This post is related to specialty Infectious Disease. Below is a list of some physicians related to this specialty.