A National Study Exploring the Association Between Fasting Duration and Mortality Among the Elderly

Abstract

Abstract Background Benefits from weight management have been widely accepted, and prolonged fasting duration has become a common method for weight control. The suitability of prolonged fasting duration for elderly individuals remains controversial. This study aims to examine the correlation between fasting duration and mortality within a nationally representative cohort of elderly individuals in the United States. Methods Data were extracted from a prospective cohort study conducted within the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Individuals over 60 with complete data on dietary intake and mortality follow-up information were included. Fasting duration was assessed using two 24-hour dietary recalls. All participants were categorized into fasting duration quantiles. Mortality outcomes were ascertained through the National Death Index. Cox proportional-hazards regression models were utilized to analyze the association between fasting duration and mortality. Results The final analysis included a total of 9,826 elderly participants (mean age 70.03, 49.33% male), with 2408 deaths observed during a median follow-up of 6.82 years. Following adjustments for covariates, the longest fasting duration (> 12.5 hours) exhibited heightened cardiovascular disease (CVD) mortality (Hazard Ratios [HR], 1.30; 95% CI, 1.01–1.66) and mortality from other causes (HR, 1.52, 95% CI, 1.07–2.16) compared to those with the shortest fasting duration (< 10 hours). Notably, the CVD mortality was significantly increased in males and in individuals aged 60–69 with a fasting duration exceeding 12.5 hours (HR, 1.49 and 2.87; 95% CI, 1.00-2.20 and 1.32–6.23, respectively). A non-linear relationship was observed between fasting duration and all-cause mortality (P = 0.03), with a fasting duration of 11.89 hours linked to the lowest mortality. Conclusions Prolonged fasting periods are associated with increased cardiovascular mortality and mortality from other causes. Fasting duration of 11.89 hours is associated with the lowest mortality rate. Caution should be exercised by clinicians when recommending time-restricted feeding for the elderly. Further research through randomized controlled trials should be conducted to comprehensively investigate the impact of TRF on mortality.