Research shows how obesity fosters COVID infection and illness

Learn from this research and, if appropriate, lose weight

Other than being 65 and older, a very big risk factor for getting seriously ill with COVID is being obese or overweight.  Almost from the beginning of the pandemic there was data showing that high fractions of hospitalized patients, roughly 30%, were obese or overweight.  Only now, with a recent medical research article do we know why.

Here is the ugly US reality.  More than two-thirds of American adults are obese or overweight.  This puts them at elevated risk of severe COVID-19 illness and death. Obesity in particular may triple the risk of hospitalization from the disease.

Here are the key findings:

==The coronavirus can directly infect fat cells.

==That in turn may activate a harmful cascade of inflammation that damages other organs, such as the heart or lungs.

==Body fat should be seen as an active tissue rather than an inert mass.

==The virus infects certain macrophages — immune cells that can trigger inflammation — in and around the fat tissue.

==Noticed was a dramatic inflammatory response shortly after the infection took hold, including an increase in several inflammatory molecules associated with severe COVID.

==Virus concentrations in fat tissue samples were relatively on par with concentrations in heart and kidney samples, though lower than concentrations in lung samples.

==Because obese and overweight people have more body fat, their fat cells could give the coronavirus more opportunities to replicate or promote inflammation.

==The researchers also theorized that obesity could contribute to long COVID, characterized by persistent symptoms, such as fatigue, body aches, chest pain, or shortness of breath, that last weeks, months or much longer after the original infection.

The big conclusion of the new study: “Our work provides the first in vivo evidence of SARS-CoV-2 infection in human adipose tissue and describes the associated inflammation.”  One of the study authors noted: “We’re seeing the same inflammatory cytokines that I see in the blood of the really sick patients being produced in response to infection of those tissues.”

Dr. William Schaffner, a professor of infectious diseases at the Vanderbilt University School of Medicine, said "The fat itself may actually become a reservoir for the virus and somehow be involved in its inflammatory response."

Michael Toole, an epidemiologist at the Burnet Institute in Melbourne, said that by serving as a reservoir, the fat cells may be effectively “hiding” COVID-19 and spreading it to other areas in the body, increasing the risk that patients suffer from long-COVID symptoms months after they recovered from their initial infections.”

“This paper is another wake-up call for the medical profession and public health to look more deeply into the issues of overweight and obese individuals, and the treatments and vaccines we’re giving them,” said Barry Popkin, a professor of nutrition at the University of North Carolina at Chapel Hill.  Indeed, it has been a major failure of the entire public health system that addressing obesity and overweight have not been priorities of pandemic management.

“Maybe that’s the Achilles’ heel that the virus utilizes to evade our protective immune responses — by hiding in this place,” said Dr. Vishwa Deep Dixit, a professor of comparative medicine and immunology at Yale School of Medicine,

Bottom line: In addition to taking vitamin D and other vitamins and supplements, losing weight should be seen as a critical way to fight COVID.