A new study presented at an American Heart Association conference suggests that restricting eating to eight hours or fewer a day, a type of intermittent fasting, may increase the risk of dying prematurely from heart disease over the long term. The study analyzed data from over 20,000 adults and found that those who consumed all their food in eight hours or less were almost twice as likely to die from cardiovascular disease compared to those who spread their eating out over 12 to 16 hours a day. Despite the popularity of intermittent fasting and its association with better health, this study raises concerns about potential negative health impacts.
There are different types of intermittent fasting, with 16:8 and 5:2 being among the most popular. The 16:8 method involves fasting for 16 hours and eating over the course of eight, while the 5:2 method involves eating only 500 calories two days a week and following a normal diet on the other days. While intermittent fasting has been associated with weight loss, improved blood sugar regulation, decreased blood pressure, cholesterol, resting heart rate, inflammation, this new study highlights the need for caution when practicing this eating pattern.
The study utilized data from the National Health and Nutrition Examination Survey (NHANES) and found that individuals who consumed all their food in eight hours or less each day were 91% more likely to die from heart disease compared to those who spread their eating out over 12 to 16 hours. The results were unexpected to the researchers, who had anticipated that time-restricted eating would be associated with lower cardiovascular risk based on previous short-term studies. The researchers believe that the intermittent fasting group may have had less lean muscle mass, which has been linked to a higher risk of cardiovascular death in previous research.
Nutrition experts note that restricting eating to eight hours a day with intermittent fasting can lead to extreme hunger and increased cravings, potentially resulting in unhealthy food choices. However, there are also limitations to the study, such as being based on just two days of dietary recall and not accounting for the number of calories consumed. The true impact of cramming all eating into eight hours or less remains unclear, as other factors could have contributed to the increased risk of death. The researchers stressed that it’s too early to make specific recommendations based on this study alone.
While short-term studies on intermittent fasting have shown positive effects on health indicators such as insulin resistance, belly fat, and blood lipid profiles, the long-term implications of this eating pattern remain uncertain. Researchers emphasize the need for more detailed and real-time dietary information in future studies to draw more definitive conclusions. Despite the surprising findings of this study, other experts caution against making clinical recommendations based on imperfect data collection methods and the complex nature of dietary habits.
