Intermittent fasting, a diet that involves alternating between voluntary fasting and non-fasting periods, might be connected to a higher likelihood of dying from heart disease, according to a recent analysis.
The analysis, first presented Monday at the American Heart Association’s scientific sessions in Chicago, found that people who limit the time they spend eating to less than eight hours per day had a 91 percent higher risk of fatal cardiovascular disease compared to those who eat over 12 to 16 hours a day.
The increased risk of cardiovascular death was also observed in individuals with pre-existing heart disease or cancer, researchers noted. Those with existing cardiovascular disease who ate between eight and 10 hours per day also had a 66 percent higher risk of death from heart disease or stroke, the analysis stated.
Intermittent fasting, which involves consuming food within a six-to-eight-hour window and fasting for the remaining 16 to 18 hours, has gained popularity over the past decade. Studies have indicated the diet can aid in weight loss, reduce the risk of illnesses like cancer, lower blood pressure, and increase energy levels.
The analysis, conducted by researchers from Shanghai Jiao Tong University School of Medicine in China, is based on the Centers for Disease Control and Prevention’s data of 20,000 adults across the United States from 2003 to 2018. It has not yet been peer-reviewed or published in an academic journal. Nonetheless, it is among few to specifically examine the long-term effects of intermittent fasting on the risk of death from cardiovascular disease.
“Limiting daily eating time to a short period, such as 8 hours per day, has gained popularity in recent years as a way to shed pounds and enhance heart health,” senior study author Victor Wenze Zhong, Ph.D., stated. “However, the long-term health effects of time-restricted eating, including risk of death from any cause or cardiovascular disease, are unknown.”
Zhong said researchers were “surprised” to find that individuals who adhere to an intermittent fasting diet had a higher risk of cardiovascular death.
“Despite the popularity of this type of diet due to its potential short-term benefits, our research clearly shows that, compared to a typical eating time range of 12-16 hours per day, a shorter eating duration was not linked to living longer,” he wrote.
Zhong said the findings should prompt individuals to be more cautious about their dietary choices and emphasized that these choices should be “aligned” with an individual’s health status.
The findings do not imply that intermittent fasting caused cardiovascular death, and further research should explore the “biological mechanisms” behind the links between the diet and negative cardiovascular outcomes, he added. He noted that the research also relies on individuals’ recollection of what they consumed.
Zhong told NBC News it is premature to lay out specific recommendations based on the analysis, writing to the outlet, “Adopting intermittent fasting for a brief period such as 3 months may likely lead to benefits in reducing weight and improving cardiometabolic health.” He emphasized that people should exercise “extreme” caution regarding intermittent fasting for longer periods, NBC News reported.
