Regular fasting was linked with a longer life and lower incidence of heart failure in heart patients, a new study has found, adding to the body of research of medical benefits of regularly skipping meals.
The findings were presented at the 2019 American Heart Association Scientific Sessions in Philadelphia on Saturday. Previous research has shown that fasting can improve symptoms of diabetes, reduce inflammation and may even delay the symptoms of Alzheimer's.
Even one day of fasting a month — when done over a lifetime — can have a profound impact on heart health because cardiovascular disease usually develops so gradually, said Benjamin Horne, the new study’s lead author.
“So you can imagine a low amount of fasting over a period of decades may be counteracting the low amount of development of the disease,” Horne, director of cardiovascular and genetic epidemiology at the Intermountain Healthcare Heart Institute in Salt Lake City, Utah, told TODAY.
“Heart disease is a long-term disease, so we want to find something that is a sustainable regimen that people can do for most of their life and build up a small amount of benefit each time they do it, have that accumulate and become a large benefit over the lifetime.”
For the new study, researchers asked 2,001 patients who underwent cardiac catheterization in Utah about their history of fasting. The state is unique on this front because many residents are members of the Church of Jesus Christ of Latter-day Saints and typically fast the first Sunday of the month as part of their faith.
About 40% of people in the group were routine fasters or previous fasters who fasted for 24 hours once a month for decades, eating nothing and drinking only water on that day. All of the participants were followed for almost five years to see if they developed new heart problems or passed away.
The routine fasters — who had been following the once-a-month regimen for more than 40 years on average — had a “substantially lower risk of death” compared to the others, even when adjusting for factors like smoking and alcohol use, Horne said. They also had a lower incidence of heart failure.
“We were surprised by the strength of the findings,” Horne said, cautioning they don't prove causality. “Observational research is not perfect, but it’s giving us a really good reliable signal that there is some survival benefit happening from fasting.”
Fasting for at least 12-14 hours activates various beneficial mechanisms in the body — lowering blood pressure, reducing anemia and triggering autophagy, a mechanism that helps to regenerate cells, he noted.
How to try intermittent fasting:
Always talk with your doctor first, especially if you’ve been diagnosed with a chronic disease. Fasting is a stressor on the body, especially if you’re doing it several days a week or 16 hours a day.
People who should not be fasting include very young children, frail older adults, pregnant women and breastfeeding women, Horne said.
Consider the various intermittent fasting plans. Popular versions include:
- The 16:8 diet, or time-restricted feeding, where you fast for 16 hours a day, but are free to eat whatever you want in the other eight hours.
- Alternate day fasting, which means eating nothing or limiting yourself to 500 calories one day, then eating whatever you want the next, and then repeating that process.
- The 5:2 plan, which means incorporating two non-consecutive fast days into your week, then eating normally during the other days.
Fasting one day a month, as many people did in the new study, is much less rigorous than fasting a few times a week, but it's very sustainable over the long term, Horne said. He's now conducting a trial to see how eating nothing for 24 hours once a week affects people with high cholesterol.