A new study suggests that restricting eating to eight hours or fewer per day, a form of intermittent fasting, may increase the risk of premature death from heart disease over the long term.

The study, presented at an American Heart Association conference in Chicago, analyzed data from over 20,000 adults and found that those who consumed all their food in eight hours or less were nearly twice as likely to die from cardiovascular disease compared to those who spread their eating over 12 to 16 hours a day.

Intermittent fasting, or time-restricted eating, has gained popularity for its potential health benefits, including weight loss and improved blood sugar regulation. However, this study raises questions about its long-term effects on heart health.

The researchers used data from the National Health and Nutrition Examination Survey and the National Death Index, focusing on participants aged 20 and older. They found that those who practiced eight-hour restricted eating were 91% more likely to die from heart disease than those with longer eating windows.

While previous short-term studies have shown benefits of intermittent fasting, this new research suggests caution for those practicing it long term. Experts note that extreme hunger and cravings could lead to unhealthy food choices, which may contribute to the increased risk of cardiovascular death seen in the study.

However, some experts caution that the study has limitations, such as relying on two days of dietary recall and not accounting for calorie intake. More research is needed to fully understand the impact of intermittent fasting on health and longevity.