COVID and obesity have been a hot topic in the past few weeks. As Covid infections continue to skyrocket across the United States and the rest of the world, more research has been appearing on potential risk factors and complicating factors for COVID-19 and the severity of the disease.
COVID and Obesity Research
A few weeks ago, Kaiser Permanente published a study 1 in the Annals of Internal Medicine that looked at the medical organization’s experience with overweight and obese patients that developed COVID-19 infections. The retrospective study looked at outcomes in Kaiser Permanente patients in Southern California with COVID-19 infections over a 10 week period from mid-February 2020 to the beginning of May 2020. The researchers found that in the almost 7000 patients, obesity was a strong correlation for worse outcomes with COVID-19 infections.
In fact, patients that were morbidly obese with a BMI (body mass index) between 40-44 kg/m2 had twice the death rate than normal-weight patients. Even more concerning, extremely morbidly obese patients with BMI great than 45 kg/m2 had double the risk of death compared to the morbidly obese group.
So why would excess fat and obesity potentially play such a large role in the significant increase in deaths in obese COVID patients? One theory may be that adipose tissues have a higher level of angiotensin-converting enzyme (ACE) 2 protein which has been shown as a potential docking protein for SARS-CoV-2 and mechanism for the virus to enter a cell. The fat cells could then potentially act as a center for viral replication which would significantly increase SARS-CoV-2 viral load in obese patients.
The Kaiser study matches similar results from a July 2020 retrospective study also published in the Annals of Internal Medicine 2 from Columbia University in New York that looked at rates of intubation and death in patients hospitalized with COVID-19 over a 45 day period in New York City. This study also found that obese patients with COVID-19 had a higher rate of intubations and death than normal-weight patients. Obese patients younger than 65 had significantly higher intubation and death rate. This Columbia study didn’t find any significant increase in inflammatory markers in the obese COVID patients, which I found surprising since some had theorized that obesity and chronic metabolic disease may predispose these patients to a higher inflammatory state and thus lead to worse outcomes from COVID-19.
A meta-analysis of 75 previously published studies regarding COVID and obesity as well as other metabolic risk factors was published in the Obesity Reviews journal 3 This study also found that obesity increased the risk for severe complications from COVID-19, but the study also found that obese people were more likely to test positive for COVID-19 and more likely to be hospitalized for COVID-19 infections.
Out of the 75 studies included in this meta-analysis, 20 of the studies looked at the impact of obesity on COVID-19 infections and complications. Eighteen of the studies found that being obese was a risk factor for worse outcomes with COVID-19 infections. These study findings of obesity as an independent risk factor for worse COVID-19 outcomes matches previous experience with severe influenza infections like H1N1 4 (opens in a new tab)" href="https://pubmed.ncbi.nlm.nih.gov/21208911/))" target="_blank" rel="noreferrer noopener nofollow" class="rank-math-link">https://pubmed.ncbi.nlm.nih.gov/21208911/)) and MERS (Middle Eastern Respiratory Syndrome coronavirus. 5
The real question that remains unanswered is specifically why obesity results in worse outcomes with COVID-19 while we don’t see worse results associated with obesity and other diseases like tuberculosis.
In any event, there’s clear science that being obese puts you not only at a higher risk of testing positive for COVID-19, but also having a potential worse course, including hospitalization, admission to an intensive care unit, intubation and death.
So how do we begin to fix this problem of COVID and obesity outcomes?
COVID-19 has exposed how unhealthy a large segment of our population is, especially here in the United States. Years of incorrect nutritional advice to eat more carbs and less fat has led us to this firestorm of obesity and metabolic disease colliding with a world-wide pandemic.
It’s time to focus on leading the public back to better dietary choices like a low carbohydrate, ketogenic diet for improved health and wellness.
There’s also concerns now about possible long-term heart issues in athletes with COVID-19.