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Why Are Obese People More At Risk Of Contracting COVID And Succumbing To It?

Mitchelle Morgan

Updated on - Written by
Medically reviewed by Melissa Mitri, MS, RD

Believe it or not, when the Corona pandemic broke out, obese people were more affected by the virus. The virus became more severe the heavier one was, and they were more likely to succumb to the attack.

However, weight isn’t the only factor at play. If you had life-threatening health conditions like diabetes or hypertension, the attack would be even more severe. So much so that if you were obese and had either of these two conditions along with other life-threatening diseases, the virus would kill you as soon as it entered your system.

Fat tissue plays a beneficial role in a healthy person, serving as a source of energy during periods of food depletion. It also secretes anti-inflammatory and protective factors in lean, healthy people. The immunity cells can also be found in fat tissue.

If fatty tissue becomes unhealthy, as it often does in obese people, it can become self-destructive and produce hormones and other chemical signals that promote chronic low-grade inflammatory responses.

The normal inflammatory response is self-limiting. The natural body’s function responds to infection, damaged cells, and other threats.

Chronic inflammation, therefore, increases the risk of issues in immunity, promotes specific cancers, heart diseases, pancreatic, respiratory system, digestive system, and reproductive system issues, among other things.

It could also explain why a high body mass index (BMI) is linked to a poorer prognosis from infectious diseases, such as COVID-19.

So here are some of the medical facts that link the progression of Covid amongst obese patients according to studies:

Coronavirus Infects Fat Cells

Covid-19 has been discovered to infect fat cells directly, according to a group of researchers. This was due to a non-peer-reviewed study[1] that claimed overweight people were more likely to die from the virus.

This is the case mainly because of the heightened body inflammatory response in obese patients. And so, when they get attacked by the virus, they have a more challenging time fighting off the infection. The lead author of this study, Dr. Catherine Blish, confirmed this to Reuters[2].

This study revolved around the adipose tissues, commonly referred to as fat cells from patients that succumb to Covid-19. And the findings indicated that the virus also inflamed the fat cells. They concluded that overweight people might become severely challenged when they get the virus.

Fat Cells Act As Viral Reservoirs Infecting Neighboring Tissue

The unfortunate part about this is that nothing stays inside fat cells. Instead, they spread to the neighboring tissue. They store this virus, and obesity does not make it easy to fight. So this means that the virus could lead to severe acute disease and long-COVID syndrome.

The fat cells act as a viral reservoir, facilitating the hiding of the COVID-19 virus, thus spreading it to other parts of the body. And this increases the likelihood of suffering long-COVID symptoms[3]. Unfortunately, these effects are felt even after recovering from the infection. This remark was brought to light by an epidemiologist at the Burnet Institute in Melbourne, Michael Toole.

On that same note, Michael Toole suggested that if the study was peer-approved, there could be a need to change current treatment methods. Most treatments to fight the virus do not generally target the fat cells. And since the virus might use the adipose tissue as a hiding ground, this might be an issue.

Inflammatory cascade

This is yet another explanation as to why obese people are at greater risk when Coronavirus attacks the fat cells. When fat cells are overloaded with nutrients, intercellular stress occurs, which can set off an “inflammatory cascade[4].”

According to Andrew Greenberg, director of the obesity laboratory at Tufts University’s Jean Mayer USDA Human Nutrition Research Center on Aging, people with obesity store immune system cells in the fat cells. They also begin to release more than average as they grow. These travel through the bloodstream and attach to the liver and muscle immune cells. As a result, inflammatory factors are triggered.

The body gets a hard time detoxifying dead fat cells in obese bodies

Another mechanism includes macrophages, which are immune cells that infiltrate fat cells. When engorged fat cells die, the body has difficulty getting rid of the tissue. This causes many toxic effects and sets off a chain reaction in which all kinds of bad things occur.

As a result, the COVID-19 process of healing, even after the symptoms have been dealt with, is slowed.

Kenneth Walsh, a University of Virginia School of Medicine professor of biochemistry and molecular genetics, had sentiments. He addressed this as a likely reason that the COVID-19 virus affects obese people more, linking it mostly to age and inflammation.

He says;

“A lot of that might be due to the process known as ‘inflammaging.’ When you get to the bottom of lots of diseases, they have an underlying inflammatory component to them.”

Walsh claims that the immune system becomes “corrupted” over time, becoming passive, overactive, or a hybrid of the two. Obesity appears to hasten this process.

What The Study Reveals About Obesity

As Michael Toole puts it, this study gives a lot of evidence that obese people need to focus on the fight against COVID-19. He continues by saying, “I would definitely include the morbidly obese in the most [at risk] groups. “We’ve known that obesity is the No. 1 risk factor for severe disease for some time, followed by diabetes and some other chronic disease, but obesity stands out.”

And he’s not the only one.

Nutrition professor Barry Popkin of the University of North Carolina at Chapel Hill agrees. However, he focuses his argument on medical professionals and public health officials reviewing[5] the treatment and vaccines given to obese and overweight people.

Around 42.4 percent of the population in the United States is obese, and 73.6 percent[6] is overweight. What’s even worse, only a few states prioritize these groups when distributing vaccines.

Obesity increases the risk of COVID-19 for various reasons, including impaired immune function mainly due to inflammation. COVID is exacerbated by type 2 diabetes, frequently associated with obesity and restricted breathing.

In the best of circumstances, proper nutrition, weight control, and workouts help to strengthen the body and help mitigate obesity. These activities are even more critical during a pandemic in the fight against COVID-19.

+ 6 sources

Health Canal avoids using tertiary references. We have strict sourcing guidelines and rely on peer-reviewed studies, academic researches from medical associations and institutions. To ensure the accuracy of articles in Health Canal, you can read more about the editorial process here

  1. ​​Martínez-Colón, G.J., Ratnasiri, K., Chen, H., Jiang, S., Zanley, E., Rustagi, A., Verma, R., Chen, H., Andrews, J.R., Mertz, K.D., Tzankov, A., Azagury, D., Boyd, J., Nolan, G.P., Schürch, C.M., Matter, M.S., Blish, C.A. and McLaughlin, T.L. (2021). SARS-CoV-2 infects human adipose tissue and elicits an inflammatory response consistent with severe COVID-19. [online] Available at: https://www.biorxiv.org/content/10.1101/2021.10.24.465626v1.full [Accessed 15 Dec. 2021].
  2. ‌Reuters (2021). What you need to know about the coronavirus right now. [online] Reuters. Available at: https://www.reuters.com/world/what-you-need-know-about-coronavirus-right-now-2021-10-28/ [Accessed 15 Dec. 2021].
  3. ‌Bhf.org.uk. (2020). Long Covid: the symptoms and tips for recovery. [online] Available at: https://www.bhf.org.uk/informationsupport/heart-matters-magazine/news/coronavirus-and-your-health/long-covid [Accessed 15 Dec. 2021].
  4. Medscape.com. (2021). What is the pathophysiology of the inflammatory cascade in systemic inflammatory response syndrome (SIRS)? [online] Available at: https://www.medscape.com/answers/168943-41383/what-is-the-pathophysiology-of-the-inflammatory-cascade-in-systemic-inflammatory-response-syndrome-sirs [Accessed 15 Dec. 2021].
  5. ‌The Coronavirus Attacks Fat Tissue, Scientists Find. (2021). The New York Times. [online] Available at: https://www.nytimes.com/2021/12/08/health/covid-fat-obesity.html [Accessed 15 Dec. 2021].
  6. Anon, (2021). FastStats – Overweight Prevalence. [online] Available at: https://www.cdc.gov/nchs/fastats/obesity-overweight.htm [Accessed 15 Dec. 2021].
Mitchelle Morgan

Medically reviewed by:

Melissa Mitri

Mitchelle Morgan is a health and wellness writer with over 10 years of experience. She holds a Master's in Communication. Her mission is to provide readers with information that helps them live a better lifestyle. All her work is backed by scientific evidence to ensure readers get valuable and actionable content.

Medically reviewed by:

Melissa Mitri

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