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The #1 Cause of "Severe" COVID, Say Experts

It's another reason to get fully vaccinated.

As we enter year three of the COVID-19 pandemic, new cases—spurred by the highly contagious Delta and Omicron variants—are skyrocketing nationwide. Yet reports that Omicron is less likely to cause severe illness have many Americans feeling confused or even blasé. But pandemic fatigue can be dangerous. Safety measures are still necessary, because people who are vulnerable to severe COVID-19 are still vulnerable—and you might be raising your own risk of a severe COVID case without realizing it. These are the #1 causes of severe COVID-19—one that's beyond your control, and one you can very much do something about. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


The #1 Cause of Severe COVID

older man with dementia talking to doctor
Shutterstock / Robert Kneschke

One of the biggest risk factors for severe COVID is simply age. "Older adults are more likely to get very sick from COVID-19," says the Centers for Disease Control and Prevention. "Getting very sick means that older adults with COVID-19 might need hospitalization, intensive care, or a ventilator to help them breathe, or they might even die." 

The CDC notes that the risk of severe COVID increases for people in their 50s and rises in the following decades; people 85 and older are the most likely to become severely ill.

This risk is why it's important for older people to get fully vaccinated and boosted—along with people they live and socialize with—and practice safety measures like mask wearing in indoor public spaces and social distancing. 

But age isn't the only risk factor for severe COVID; younger people can also become severely ill from the virus. Read on for the #1 risk factor for severe COVID at any age.

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The #1 Cause of Severe COVID (At Any Age)

Doctor measuring obese man waist body fat.

Several studies have found that obesity—defined as a body mass index (BMI) over 30—increases your risk of severe illness, hospitalization or death from COVID.

The effect has even been seen in children. In a study released this month by the CDC, researchers found that nearly two-thirds of hospitalized COVID-19 patients aged 12 to 17 were obese, and their average hospital stay was twice that of non-obese adolescents.

According to a review of studies published last winter, obesity can increase your risk of dying from coronavirus by nearly 50%. Scientists analyzed 75 studies and found that obesitywas associated with a 48% higher risk of death, a 113% higher risk of hospitalization and 74% higher risk of admission to intensive care with COVID-19.

RELATED: The #1 Cause of COVID-19, According to Science 


Why Is Obesity a Risk for Severe COVID?


Obesity has been shown to increase inflammation throughout the body and impair the immune system, which has been associated with a higher death rate from other diseases like influenza. 

Besides impaired immune function, obesity is associated with high blood glucose and diabetes, another risk factor for serious COVID.

Additionally, an aspect of the risk is just physics. When you're obese, larger fat deposits in the chest wall, chest cavity and abdominal cavity compress the chest, meaning that obese people have to work harder to breathe even when they're healthy. 

"​​It's like when you're lying down and breathing, and if I sat on top of your chest and you tried to breathe. It is much harder to catch your breath when your lungs are smashed," Dr. Rekha Kumar, an obesity medicine specialist at Weill Cornell Medical College, told CNN this week. "If you're starting with a compromised respiratory system and this is a respiratory disease, you're already at a disadvantage."

RELATED: Think You Have COVID? Here's the First Thing You Should Do


But You Can Do Something About It

Side view of young female surgeon tying her surgical mask

Doctors say that, if you're overweight or obese, losing weight is one of the most important things you can do to stay healthy during the pandemic. Research backs it up.

A study published last month by the Cleveland Clinic compared people who underwent weight loss surgery to people with obesity who hadn't. The researchers found those who had the surgery had a 60% lower risk of developing severe COVID, including a  49% lower risk of hospitalization and a 63% lower risk of needing supplemental oxygen. (The scientists say it's weight loss, not the surgery, that's responsible for the reduced risk.)

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How to Stay Safe Out There

Woman with face mask getting vaccinated, coronavirus, covid-19 and vaccination concept.

Follow the fundamentals and help end this pandemic, no matter where you live—get vaccinated ASAP; if you live in an area with low vaccination rates, wear an N95 face mask, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Michael Martin
Michael Martin is a New York City-based writer and editor. Read more about Michael
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