Time-Restricted Eating Linked to a 91% Higher Risk of Cardiovascular Death

An extensive study involving over 20,000 adults in the United States reveals that adhering to a time-restricted eating plan, where individuals consume all their food in less than 8 hours daily, significantly increases the risk of cardiovascular disease mortality. This finding was presented at the American Heart Association’s Epidemiology and Prevention Lifestyle and Cardiometabolic Scientific Sessions 2024. The event, taking place in Chicago from March 18-21, focuses on the latest research in population-based health, wellness, and the impact of lifestyle choices.

Understanding Time-Restricted Eating

Time-restricted eating is a form of intermittent fasting that limits daily food intake to a specific time window, ranging from 4 to 12 hours. A common approach is the 16:8 method, where individuals fast for 16 hours and eat within an 8-hour window. Previous studies suggested that this diet could improve various cardiometabolic health markers, including blood pressure, glucose levels, and cholesterol.

Study Findings: The Risks of a Restricted Eating Window

Despite the popularity of time-restricted eating for weight loss and heart health, the long-term effects on mortality and cardiovascular health were not well-understood until now. The research, led by Victor Wenze Zhong, Ph.D., of Shanghai Jiao Tong University School of Medicine, analyzed dietary patterns from the National Health and Nutrition Examination Surveys (NHANES) and mortality data from the Centers for Disease Control and Prevention’s National Death Index.

The Study’s Alarming Findings

• A 91% increase in cardiovascular death risk for those eating within less than an 8-hour window.
• For individuals with existing heart disease or cancer, the risk remained elevated.
• A specific finding among heart disease patients indicated a 66% higher risk of death from heart disease or stroke with an eating window of 8 to less than 10 hours.
• No significant reduction in overall mortality risk was observed with time-restricted eating.
• An eating window exceeding 16 hours daily could lower cancer mortality risk among cancer patients.

The Implications of the Study

This research challenges the perceived benefits of time-restricted eating, highlighting the need for caution and personalized dietary advice, especially for individuals with pre-existing health conditions. Although the study found a correlation between an 8-hour eating window and increased cardiovascular death, causation was not established. The study emphasizes the importance of considering an individual’s health status and the latest scientific evidence when making dietary recommendations.

Study Methodology and Limitations

The study reviewed dietary information from roughly 20,000 U.S. adults, following them for an average of 8 to a maximum of 17 years. Participants, averaging 49 years old, included a balanced gender mix and diverse racial backgrounds. However, the reliance on self-reported dietary data and the exclusion of other health-affecting factors were noted limitations. Future research will explore the biological mechanisms behind these associations and if these findings hold true in different global populations.

Further Research and Commentary

Experts like Christopher D. Gardner, Ph.D., highlight the need for more detailed analysis, including the quality of participants’ diets and a comparison of demographics and baseline characteristics across different eating schedules. Such additional information could shed light on the independent effects of time-restricted eating patterns and contribute to a deeper understanding of the relationship between diet timing and cardiovascular health. Source