The obesity-COVID-19 connection: Higher weight, higher risk

It’s common knowledge that old age and certain health conditions such as diabetes and heart disease put people at increased risk of suffering severe symptoms of COVID-19. But did you know obese people who contract the virus are also more likely to become dangerously ill?

A slew of recent studies shows a profound relationship between obesity and the risk of admission to the intensive care unit, intubation and death due to the virus. This is alarming news for the more than 40% of American adults who are considered obese (defined as having a body mass index, or BMI—a measure of body fat based on height and weight—of 30 or more), including the 10 percent who are considered morbidly obese (having a BMI of 40 or more).

As BMI increases, so does the risk of death. A study of 150,000 patients with COVID-19 found hospitalizations were seven percent more likely and deaths were eight percent more likely among patients with a BMI of 30-34.9%. That increased dramatically among those with a BMI of 45 who were four times more likely to die from the virus than those of normal weight, according to a study of 7,000 COVID-19 patients published last in the Annals of Internal Medicine. 

Carrying excess weight is linked with impaired immune function and chronic inflammation, both of which can worsen COVID-19.

And people with obesity are also more likely than those of normal weight to have chronic health ailments that are risk factors for COVID-19, including hypertension, type 2 diabetes and lung disease. 

But you don’t need to be obese to be at risk of becoming seriously ill if you contract the virus. Even a few extra pounds can put you in the danger zone. The Centers for Disease Control recently issued a warning that even moderate excess weight (having a BMI of 25 or more) may increase the risk of severe illness from the virus. With 42% of Americans classified as obese and another 32% considered overweight, the U.S. has the highest prevalence of obesity of any country in thew world — this means 75% of the country’s adults are at increased risk of severe symptoms if they contract the virus.

Early on in the pandemic researchers were unsure whether excess weight in and of itself increased the chances of contracting COVID-19 or whether it was the health issues that accompany obesity that make people vulnerable. These new studies prove there’s no doubt about it: excess weight means extra risk. 

This underscores just how crucial it is to maintain a healthy weight. (People with the lowest risk of becoming severely ill from the virus have a BMI that’s typically under 25.) While wearing a mask is the first step to stay healthy in the age of COVID-19, the next best course of action is regular moderate exercise to reduce weight and thus minimize the effects of COVID-19 infection.