How Obesity Affects COVID-19


As researchers continue to learn about COVID-19, they are increasing their understanding of who is being most affected by the novel coronavirus. One unsettling revelation has been that obesity is a common factor in a significant number of cases in the U.S. and around the world.

While the implications of the obesity epidemic embedded within the pandemic of COVID-19 indeed are troubling, UCLA professor of internal medicine and director of the UCLA Center for Human Nutrition Dr. Zhaoping Li views the situation as a potential wake-up call for people to reset their eating habits.

“COVID-19 has disrupted our daily patterns,” Dr. Li says. “This is the time to reevaluate how we nourish our bodies, how that plays into our overall wellness and informs our community response.”

Obesity — defined as weight that is higher than what is considered as a healthy weight for a given height —is a global epidemic. Two-thirds of Americans are overweight or obese; by 2030, it is expected that nearly half of all adults will be obese and one-in-four will be severely obese.

Dr. Li, who also is chief of the UCLA Division of Clinical Nutrition, talks about the impact of obesity on COVID-19 and offers practical steps we can take now to better nourish our bodies and improve our health.

What is the relationship between diet, obesity and immune function?

Diet and obesity affect immune function in complex ways. Generally, those who regularly consume high-fat, high-sugar and high-salt processed foods are more likely to develop illnesses. On the flipside, eating a well-balanced diet helps your body’s ability to fight infections, viruses and other chronic conditions.

People who are obese often have respiratory problems that can include difficulty breathing, impaired blood oxygenation and low lung volume and muscle strength. They also are predisposed to diabetes, high blood pressure, pneumonia, pulmonary hypertension and cardiac stress, all of which are risk factors that can lead to poor outcomes for individuals who are diagnosed with COVID-19.

Why is it important for you to highlight the link between obesity and COVID-19?

We, as physician-researchers, are watching the data points very closely. A preliminary report published by Nature, a respected research journal, found that among 4,103 patients with COVID-19 in New York City, having a BMI greater than 40 — sometimes categorized as “extreme” or “severe” obesity — was the second-strongest independent predictor of hospitalization, after old age. The researchers also found that among 383 patients with COVID-19 in Shenzhen, China, those with obesity were more likely to require mechanical ventilation than those with diabetes or cardiovascular disease.

As the prevalence of obesity increases in the U.S., so, too, do the number of people who suffer from malnutrition. People who eat unhealthy meals consume fewer nutrients and over the long-term develop impaired immune function, which makes it difficult for them to fight off an illness like COVID-19.

What do you tell your patients?

I try to remind my patients that we are settling into a reality in which this virus will be with us for a long time. If you feel like you don’t have regular eating patterns, try placing structure around how and when you eat. This can include planning for meals ahead of time or writing down what you have eaten after a meal is consumed.

How can we all live a healthier lifestyle?

Focus on overall wellness. Eat colorful fruits and vegetables, cut down on refined starches, avoid foods with hidden fats, get adequate sleep and design a personal exercise program that you can stick with. If you need help, talk to your primary care physician; he or she can provide you with information about resources that are available to you.

What essential advice would you give to someone who has decided to make a change?

It is vital for everyone to do whatever they can now to strengthen their immune health. It looks like there will be a significant period of time before a vaccine is developed, and strengthening the immune system will help us all safely reenter a “new normal” as stay-at-home guidelines are loosened. Now is the time to think about addressing obesity as part of our societal response to COVID-19.