Does intermittent fasting for 8 hours really work?
An abstract published by the American Heart Association on Monday, March 18, showed that over 20,000 adults who followed an 8-hour time-restricted eating schedule—a type of intermittent fasting—had a 91 percent higher risk of death from cardiovascular disease.
“Overall, this study suggests that time-restricted eating may have short-term benefits but long-term adverse effects. When the study is presented in its entirety, it will be interesting and helpful to learn more of the details of the analysis,” said Christopher D. Gardner, Ph.D., FAHA, the Rehnborg Farquhar Professor of Medicine at Stanford University in Stanford, California, and chair of the writing committee for the Association’s 2023 scientific statement, Popular Dietary Patterns: Alignment with American Heart Association 2021 Dietary Guidance.
The study also stated that people with heart disease or cancer also had an increased risk of cardiovascular death.
Compared with a standard schedule of eating across 12-16 hours per day, limiting food intake to less than 8 hours per day was not associated with living longer, it added.
Likewise, people with cardiovascular disease who follows restricted eating schedule additionally had a 66 percent higher risk of death from heart attack or stroke.
“One of those details involves the nutrient quality of the diets typical of the different subsets of participants. Without this information, it cannot be determined if nutrient density might be an alternate explanation to the findings that currently focus on the window of time for eating. Second, it needs to be emphasized that categorization into the different windows of time-restricted eating was determined on the basis of just two days of dietary intake,” Gardner said.
Senior study author Victor Wenze Zhong, Ph.D., a professor and chair of the department of epidemiology and biostatistics at the Shanghai Jiao Tong University School of Medicine in Shanghai, Chinap, said that restricting daily eating time to a short period, such as 8 hours per day, has gained popularity in recent years as a way to lose weight and improve heart health.
“However, the long-term health effects of time-restricted eating, including risk of death from any cause or cardiovascular disease, are unknown,” he said.
In this study, researchers investigated the potential long-term health impact of following an 8-hour time-restricted eating plan.
They reviewed information about dietary patterns for participants in the annual 2003-2018 National Health and Nutrition Examination Surveys (NHANES) in comparison to data about people who died in the US from 2003 through December 2019, from the Centers for Disease Control and Prevention’s National Death Index database.
Future research may examine the biological mechanisms that underlie the associations between a time-restricted eating schedule and adverse cardiovascular outcomes, and whether these findings are similar for people who live in other parts of the world, the authors noted.
Image credits: Stephanie Frey | Dreamstime.com