People who have practiced intermittent fasting for decades experience less severe complications from COVID-19

A new study has found that COVID-19 patients who practiced regular water-only intermittent fasting for decades had a lower risk of hospitalization or dying due to the virus, than patients who did not.

The research, published in the journal, BMJ Nutrition, Prevention & Health was conducted by Intermountain Healthcare in Salt Lake City, Utah.

“Intermittent fasting has already shown to lower inflammation and improve cardiovascular health," said Benjamin Horne, PhD, director of cardiovascular and genetic epidemiology at Intermountain Healthcare in a statement. "In this study, we’re finding additional benefits when it comes to battling an infection of COVID-19 in patients who have been fasting for decades."

Researchers identified patients enrolled in the INSPIRE registry, a voluntary health registry at Intermountain Healthcare, who had also tested positive for COVID-19 between March 2020 and February 2021 — before vaccines were widely available.

They engaged 205 patients who had tested positive for the virus. Of those, 73 said they regularly fasted at least once a month. Researchers found that those who practiced regular fasting had a lower rate of hospitalization or death due to the coronavirus. According to Horne, intermittent fasting was not associated with whether or not someone tested positive for the virus, but it was associated with lower severity once someone had tested positive.

In this study, participants who said they regularly fasted did so for an average of more than 40 years. Intermountain researchers had the opportunity to closely study this specific cohort of long-time intermittent fasters because a large portion of its patients fast regularly for religious reasons.

Nearly 62 percent of Utah’s population belongs the Church of Jesus Christ of Latter-day Saints, whose members typically fast the first Sunday of the month by going without food or drink for two consecutive meals.

While Horne said that more research is needed to understand why intermittent fasting is associated with better COVID-19 outcomes, he said fasting reduces inflammation, especially since hyperinflammation is associated with poor COVID-19 outcomes. In addition, after 12 to 14 hours of fasting, the body switches from using glucose in the blood to ketones, including linoleic acid.

“There’s a pocket on the surface of SARS-CoV-2 that linoleic acid fits into – and can make the virus less able to attach to other cells,” he said, adding that another potential benefit is that intermittent fasting promotes autophagy, which helps the body destroy and recycle damaged and infected cells.

Horne stressed anyone who wants to start intermittent fasting should consult with their doctor and practitioners should remind patients these results are from people who have been fasting for decades. In addition, he said, fasting is not a substitute for a COVID-19 vaccination.

“It should be further evaluated for potential short and long-term preventative or therapeutic use as a complementary approach to vaccines and anti-viral therapies for reducing COVID-19 severity,” Horne said of intermittent fasting.