When a pandemic and an epidemic collide

The impacts of COVID-19 on gut microbiota and the double burden of malnutrition

We’ve become familiar with the possible long-term effects of COVID-19 on heart, lung and brain health, but of growing concern is the impact the pandemic is having on nutritional health. Researchers Paula Littlejohn and Dr. Brett Finlay of the Finlay Lab, at the Michael Smith Laboratories, at the University of British Columbia are exploring the important effect that COVID-19 is having on our gut microbiome. Their findings have them concerned about how these impacts amplify malnutrition globally. 

The Double Burden of Malnutrition explained 

PhD Candidate Paula Littlejohn

The double burden of malnutrition (DBM) is defined by the World Health Organization as “…the coexistence of undernutrition along with overweight and obesity, or diet-related noncommunicable diseases, within individuals, households and populations, and across the life course.” This phenomenon was studied during the 1970s and 80s within low to middle income countries and showed a rise of people dying from non-communicable diseases (such as type II diabetes, diet-related cardiovascular disease etc.). At this time, Dr. Barry Popkin developed the concept of the “nutrition transition” which describes a shift towards diet and actives linked with obesity. 

The coexistence of undernutrition and overnutrition in low–to–middle income countries is on the rise. And research has established the connection between exposure to malnutrition early in life and a predisposition to non-communicable, nutrition-related diseases. 

“You can have malnourished and obese people living the same household, or you can have an individual that is both obese and anemic,” explains researcher Paula Littlejohn. “One concern is that the gut microbiome might also be playing a role in this.”

The microbiome is the genetic material (bacteria, fungi, protozoa and viruses) that live on and inside the human body. The gut microbiome is hugely important to our overall health, aiding in digestion, bolstering our immune system and contributing to other aspects of our health. 

So how has the double burden of malnutrition been impacted by the COVID-19 pandemic and what does this mean for our gut microbiome? 

Dr. Brett Finlay

This is exactly what Dr. Finlay and Paula Littlejohn are exploring in their recent paper When a pandemic and an epidemic collide: COVID-19, gut microbiota, and the double burden of malnutrition. With the DBM on the rise before the pandemic, there is growing concern that the restrictions put in place to help control the spread of COVID-19 are having a significant impact food security. 

The loss of school lunch programs, households forced into poverty with massive job cuts, industry shut downs, restricted passage of goods and humanitarian aid being slowed due to border closures, all of this adds up to preventing access to healthy food for many. Some families are forced to sacrifice food quality  for cheaper options and are left with unhealthy choices that exacerbate the malnutrition problems already existent in their communities. And food is the biggest modulator of our microbiome. 

What are the impacts of COVID-19 on our gut microbiome? 

There are direct connections between COVID-19 and our gut microbiome. The ACE2 receptor found in our nasal and lung cells is the same as the one found in our gut. This means that the SARS-CoV 2 virus can also find a home in our gut. Once in the gut, the virus can further replicate causing gastrointestinal symptoms such as nausea and diarrhea. This can exacerbate pre-existing malnutritional problems (i.e., someone with chronic diarrhea), leading to further loss of nutrients and more severe forms of malnutrition. COVID-19 can shift the gut microbiome into a dysbiotic state, increasing inflammation and the development of related diseases (such as type 2 diabetes). 

The team’s research into the connection between COVID-19, the DBM and gut health illuminates the complexities of the relationship. “It all kind of ties back in, it’s like a big circle. COVID-19 restrictions to limit virus spread impacts access to food, access to resources and it also directly impacts our health via the gut microbiome,” says Littlejohn. Hopefully bringing awareness to these connections will cause people to pay more attention to the importance of the gut microbiome as a whole. There are several initiatives that promote gut health that this research hopes to lend support to. Shifting away from convenient, low quality food choices to healthy ones, encouraging breastfeeding, and even getting out into nature all contribute to a healthy gut microbiome. Littlejohn and Finlay also aim to raise more awareness across the global community about the challenges of the DBM. 

What can we be doing to protect ourselves from the impacts the restrictions of the COVID-19 pandemic are having on our health? 

There are many small things we can do to preserve our gut microbiome day to day. “Maintaining diversity in your diet is essential. Even though we are at home a lot more and tempted to eat all the ice cream in the freezer, we need to avoid those poor choices. Cut up fruits and vegetables and make them easy and available to yourself in your home,” advises Littlejohn. Exercise and stress also shifts our microbiome. Getting outside can both provide exercise and stress relief which will help to diversify and build up our gut health. Many helpful microbes can be found in  the soil.  Playing in the garden and not immediately washing your hands is a very simple activity that can contribute positively to your microbiome. “As Dr. Brett Finlay says in his book on the subject, Let Them Eat Dirt, it’s ok to let kids play in the dirt. We need to stop being overly sanitized when we’re in our homes and use precautions when in busy public spaces,” suggests Littlejohn. 

The larger systemic issues that have created the DBM are problems that will take time to be addressed. Finlay and Littlejohn aim to raise more awareness about these issues with their continued research on the gut microbiome and its relationship to COVID-19. For the time being, there are many small steps we can take as individuals to be proactive about protecting our health, despite the restrictions put in place during this pandemic.