Optimal - The Blog
July 1, 2025
According to preliminary results from a study of more than 20,000 adults age 20 or older, intermittent fasting, restricting eating to an 8-hour period rather than a 12-16-hour period, was associated with a 91% increase in cardiovascular mortality risk. The data was obtained from 2003-2018 NHANES surveys and self-reporting of food intake.
The analysis found:
- Subjects had a 91% higher risk of death due to cardiovascular disease when consuming all of their daily food intake within 8 hours.
- The increased CVD mortality risk was also observed for subjects with heart disease or cancer.
- A 66% greater mortality risk from heart disease or stroke was observed in those with existing CVD who restricted their eating to 8-10 hours per day.
- Time-restricted eating did not reduce the overall risk of death from any cause.
- Cancer mortality for those with cancer was lower in subjects consuming their daily food intake over 16 or more hours per day.
According to senior author Victor Wenze Zhong, PhD, “We were surprised to find that people who followed an 8-hour, time-restricted eating schedule were more likely to die from cardiovascular disease. Even though this type of diet has been popular due to its potential short-term benefits, our research clearly shows that, compared with a typical eating time range of 12-16 hours per day, a shorter eating duration was not associated with living longer.”
However, further research and peer-reviewed studies are needed to draw firm conclusions from the data obtained.
Reference
American Heart Association. 8-hour time-restricted eating is linked to a 91% higher risk of cardiovascular death. American Heart Association Epidemiology and Prevention|Lifestyle and Cardiometabolic Health Scientific Sessions 2024, Abstract P192. https://newsroom.heart.org/news/8-hour-time-restricted-eating-linked-to-a-91-higher-risk-of-cardiovascular-death#:~:text=The%20analysis%20found%3A,of%20death%20from%20any%20cause
Harris, Emily. “Study Examines Intermittent Fasting and Cardiovascular Mortality.” JAMA vol. 331,17 (2024): 1440. doi:10.1001/jama.2024.5158
