During the past century, persons aged >70 years represented the fastest growing segment of the US population with the life expectancy of older Americans steadily increasing, until the onset of COVID-19 in 2020. Unfortunately, the increase in lifespan has not been accompanied by an increase in health-span, which is the time-period in which a person is healthy and functionally independent. Rather, the aging population has been accompanied by an increase in the number of individuals living with chronic metabolic and neurocognitive disease conditions, including obesity, metabolic syndrome, and Alzheimer's disease and Related Disorders (ADRD). Moreover, poor metabolic health appears to be a risk factor for accelerated brain aging; therefore improving metabolic health may represent a strategy to improve long-term brain health.~Although age-related biological and metabolic changes clearly have a role in the development of chronic health conditions and risk for ADRD, a growing body of research indicates lifestyle factors contribute to modifiable patho-physiological states that precede the development of many age-related chronic health conditions. Specifically, over-nutrition, sedentary lifestyle, and poor sleep habits have been directly linked with metabolic diseases, as well as cognitive decline and development of ADRD in later life.~Our work and that of others has demonstrated that the rate of functional decline among older adults is highly influenced by biological and metabolic changes during aging, which are largely affected by lifestyle factors, namely dietary intake, sleep, and physical activity levels. Specifically, the investigators have shown that intermittent fasting (IF) regimens, particularly time restricted eating (TRE), can have positive effects on biological, metabolic, and functional health markers in middle-aged and older adults, similar to that of calorie restriction. These observations raise the possibility that interventions targeting the fundamental biology of human aging have the potential to delay, if not prevent, the onset of aging-associated conditions, such as ADRD. The unprecedented growth of the aging population has created an urgent need for promising interventions that can preserve older adult's capacity to live independently and function well.~The scientific premise of this proposal is that a time-restricted eating intervention can target the cellular and metabolic alterations that underlie age-related metabolic and neurocognitive disease conditions and thereby extend health-span in the growing population of older adults who reported subjective cognitive decline.
Grounded in the principles of geroscience, the proposed Fasting ENHANCE study will test whether a time restricted eating (TRE) regimen can improve cognitive function and other aspects of successful aging in a safe and sustainable manner in at risk overweight older adults. Specifically, this study will evaluate whether TRE can improve cognitive and physical function, as well as self-reported sleep, mood, and quality of life, in overweight, older adults (age > 65 years) who are at high risk of cognitive decline due to self-reported cognitive difficulties. Eligible participants will be assigned to either a TRE intervention, in which they will be instructed to fast for a target of 16 hours per day, or a successful aging (SA) comparison group for a 24-week period.