Time-restricted Eating As A Nutrition Strategy For Individuals During Cardiac Rehabilitation: A Feasibility Study

Cardiac rehabilitation (CR) is a multi-modal program for secondary cardiac event prevention. Nutrition counselling is considered a core component of CR, where heart-healthy diets are commonly encouraged for the management of cardiovascular risk factors (e.g., body weight, blood pressure, glucose). However, many patients find it difficult to adhere to heart-healthy diets due to common barriers such as time. Time-restricted eating (TRE) is a form of intermittent fasting where individuals consume ad libitum energy intake within a set window of time, commonly 8 hours, and fast for the remaining 16 hours of the day (16:8 TRE). TRE has been shown to have positive effects on cardiovascular risk factors, may potentiate the effects of exercise, and has high patient feasibility. TRE may be an attractive addition to CR to enhance its effects on cardiovascular risk factors. PURPOSE: We aimed to assess the feasibility and safety of TRE for patients attending CR. METHODS: Men and women referred to CR for CVD (eating window >12 h/day) were enrolled in a parallel-group, randomized trial of CR only vs CR plus 16:8 TRE (CR + TRE).. Adherence to TRE was measured through participant responses to twice daily automated text messages with the times they started and stopped eating to calculate % of days with fasting >16 h. Safety was assessed as adverse events collected systematically via phone calls throughout the study. RESULTS: To date, n = 29 have enrolled, and 15 (CR + TRE, n = 7, 1 woman; CR only, n = 8, 2 women) have completed the intervention. CR + TRE participants responded to 90.3 ± 12.6% of text messages and were adherent to TRE 66.8 ± 30.1% of days. One adverse event of hypoglycemia has been reported, which was resolved by a CR physician recommending a reduction in diabetes medication. Reported TRE-related symptoms include nausea (n = 3) and dizziness (n = 1). CONCLUSION: Our preliminary findings suggest 16:8 TRE may be safe and feasible for individuals attending CR. Due to physician monitoring during CR, the occurrence of hypoglycemia in individuals with diabetes can be addressed quickly and safely. Completion of the present study will allow for a further understanding of the feasibility, safety, and benefits of TRE during CR.