Aug. 10, 2022 — Intermittent fasting wasn’t linked to a lower chance of getting COVID-19, but it was linked to less severe infection, according to a new study.
The study was conducted on men and women in Utah, averaging 60 years of age, who contracted COVID before vaccines were available.
About 1 in 3 people in Utah fasts from time to time – more than in other states. This is partly because more than 60% of the people of Utah belong to The Church of Jesus Christ of Latter-day Saints, and about 40% of them fast—usually skipping two meals in a row.
Those who fasted an average of one day a month over the past 40 years were no less likely to contract COVID, but they were less likely to be hospitalized or die from the virus.
“Intermittent fasting has already been shown to reduce inflammation and improve cardiovascular health,” study lead author Benjamin Horne, PhD, of the Intermountain Medical Center Heart Institute in Salt Lake City, said in a statement.
“In this study, we find additional benefits in controlling COVID-19 infection in patients who have been fasting for decades,” he said.
The study was published in BMJ Nutrition, Prevention & Health.
Intermittent fasting is not a substitute for a COVID-19 vaccination
Importantly, intermittent fasting should not be viewed as a substitute for a COVID vaccine, the researchers stress. Rather, regular fasting could be a health habit to consider because it’s also linked to a lower risk of diabetes and heart disease, for example.
But anyone who wants to consider intermittent fasting should consult their doctor first, Horne stressed, especially if they’re elderly, pregnant, or have diabetes, heart or kidney disease.
Fasting didn’t prevent COVID-19, but it made it less bad
In their study, the team examined data from 1,524 adults who were seen at the Intermountain Medical Center Heart Institute’s cardiac catheterization lab, completed a survey, and underwent testing for the virus that causes COVID-19 from March 16, 2020 to February 25, 2021.
Of those patients, 205 tested positive for COVID, and of those, 73 reported fasting regularly at least once a month.
A similar proportion of patients contracted COVID-19 whether or not they had regularly fasted (14% vs. 13%).
But among those who tested positive for the virus, fewer patients were hospitalized for COVID or died during study follow-up if they had been fasting regularly (11%) than if they were not fasting regularly (29%).
Even when analyzes were adjusted for age, smoking, alcohol use, ethnicity, history of heart disease, and other factors, regular fasting was still an independent predictor of a lower risk of hospitalization or death.
Several things could explain the results, the researchers suggest.
Loss of appetite is a typical response to infection, they note.
Fasting reduces inflammation, and after 12 to 14 hours of fasting, the body switches from using glucose in the blood to using ketones, including linoleic acid.
“There’s a pocket on the surface of SARS-CoV-2 that linoleic acid fits in — and can make the virus less able to attach to other cells,” Horne said.
Intermittent fasting also encourages autophagy, he noted, which is “the body’s recycling system that helps your body destroy and recycle damaged and infected cells.”
The researchers conclude that intermittent fasting schedules should be explored in further research “as adjunctive therapy to vaccines to reduce the severity of COVID-19 both during and after the pandemic, given that revaccination every few months indefinitely for.” can be done all over the world and access to vaccines is limited in many countries.”