Can weight loss help protect against the worst outcomes of COVID-19?

Yes, according to several health experts, citing a growing body of studies showing that obesity is a major risk factor for more severe illness, hospitalization and death from the coronavirus.

Obesity, defined as having a body mass index of 30 or higher, is a common, serious and costly chronic disease, according to the U.S. Centers for Disease Control and Prevention — and having it increases the risk of severe illness from COVID-19.

This factor has often been overlooked during the coronavirus pandemic, according to Dr. Scott Miscovich of Premier Medical Group.

He cited a study from the Netherlands in 2021 that found obesity to be a major risk factor for complications resulting from COVID-19, such as acute respiratory distress syndrome, clotting and “cytokine storm,” an exaggerated immune response that floods the bloodstream with inflammatory proteins.

Another study by the American Heart Association found obesity to be the top risk factor for those infected — even if they were under the age of 50 — for hospitalization, placement on ventilators and death.

This is important, Miscovich said, because many younger people remain unvaccinated, believing they are not as susceptible to the virus but may be unaware of higher risk of serious complications with obesity.

“This is a major wake-up call,” Miscovich said. “We’re not fat-shaming. What we’re trying to do is basically talk facts and give people the truth, and the truth is that if you are not vaccinated and you are significantly overweight, you are at a significant increased risk of being hospitalized, ventilated or dying of COVID.”

CDC says having obesity increases the risk of severe illness from COVID-19 and that the risk increases sharply with an elevated BMI.

An August 2020 study published in Obesity Reviews examined data from around the globe and found that obese people who contracted the coronavirus were 113% more likely to be hospitalized, 74% more likely to be admitted to intensive care and 48% more likely to die.

Also, children who are obese might suffer worse outcomes from COVID-19, the CDC said, citing a study that associated obesity with a 3.07 times higher risk of hospitalization and 1.4 times higher risk of severe illness when hospitalized.

Where Hawaii ranks

Nationally, about 42% of American adults are obese, according to the most recent CDC statistics. Hawaii, with a rate of about 24.5%, is among a handful of states in the U.S. with the lowest adult obesity rates, along with Colorado and Massachusetts.

Someone who is obese has a BMI, a calculation dividing weight by height, of 30 or higher. Many Americans also fall into the overweight category, with a BMI somewhere between 25 to under 30.

At the same time, the pandemic has fueled an increase in obesity rates for Hawaii children — to nearly 1 in 6 children ages 10 to 17 — according to a Robert Wood Johnson Foundation report, which examined inequities caused by COVID-19-related school closures.

The prevalence of obesity is also highest among adult Native Hawaiian and Pacific Islander populations, followed by non-Hispanic Blacks and those of two or more races, according to the CDC.

A separate CDC study in January found that about two-thirds of adolescents infected with the coronavirus and admitted to hospitals last summer suffered from obesity.

CDC opened up eligibility for COVID-19 vaccine boosters as early as Oct. 21 to those 18 and up with underlying medical conditions, including obesity, though most people may not have realized it.

Hawaii’s booster rate, considered a key tool in the battle against the highly contagious omicron variant, meanwhile, continues to lag, with only 34.8% of the state population boosted as of Tuesday.

Among younger generations, vaccination and booster rates are lower. Only 20.5% of Hawaii residents ages 18 to 24, and about 24% of those ages 25 to 39, have been boosted in the state.

How does obesity contribute to higher risks from the coronavirus?

While obesity is often linked to other conditions such as diabetes and heart disease, which also increase risk outcomes from COVID- 19, researchers think the coronavirus itself attacks fat tissue as well as macrophages — immune cells within body fat — which provokes an inflammatory defense response.

Dr. Hyewon Jun, an internal medicine physician at Kaiser Permanente, says excess weight triggers this amplified inflammatory response — sort of a “fight or flight” response by the body.

“We kind of have this chronic inflammation state when we have excess visceral fat,” she said.

Risks are higher when the fat is around the abdomen, organs or blood vessels, with this inflammation resulting in more serious disease from the virus. Also, excess fat pushes the diaphragm up higher in the chest, decreasing lung capacity.

Losing weight can help improve overall health, Jun said, not just in the face of the coronavirus in preventing a slew of diseases, including heart disease, cancer and diabetes.

The good news, she said, is that one does not have to go to extremes or lose an enormous amount of weight to see improvement.

“There is hope because many who struggle with this condition want to lose 50 to 100 pounds,” Jun said, “but actually 5% to 10% weight loss has health benefits. It’s an excellent start.”

Those benefits can be seen in improved metabolic conditions, blood pressure and less weight on joints.

Kaiser Permanente recommends gradual and sustainable lifestyle changes that include healthful eating with more fresh vegetables, fruits and whole grains.

People also should make physical activity a regular part of their day and keep a positive mindset, according to Jun.

“It’s really encouraging people not to get discouraged when they don’t get to this mammoth goal,” she said. “Really, for healthier weight, the biggest change is around eating healthy.”