Project Summary
Calorie restriction (CR) is defined as eating a nutritionally adequate diet that is below energy requirements. CR
has been studied for almost 100 years and has been found to extend the lifespan and healthspan of numerous
species. Further, when tested in young and middle-aged humans, modest CR improves healthspan and slows
biological aging. However, adherence to CR has been found to decrease over time, calling into question the
long-term viability of this approach. A possible alternative to CR that may have better adherence and
acceptability is time-restricted eating (TRE), which involves eating one's food in an 8 to 10-hour period of the
day. TRE extends the lifespan of rodents, and based on recent human trials, TRE improved disease risk
factors and biomarkers of aging. Further, many benefits of TRE were achieved even when weight loss did not
occur. Although several health benefits of CR and TRE have been documented, the effect of these
interventions, namely TRE, on cancer risk is unclear. Thus, the proposed administrative supplement will
support analyses aimed at addressing unanswered questions related to time-restricted eating (TRE) and CR
and cancer risk. The supplement will support awards U01 AG073204 (DiAL Health, A planning project to pilot
test and optimize dietary approaches to slow aging and design a long-term trial) and U01 AG073240 (HALLO-
P, Health Aging & Later-Life Outcomes Planning) to collect cancer-related endpoints, including cancer history
and screening, an expanded inflammatory biomarker assessment, and gut microbiome. The two parent awards
are clinical trials that are testing the effects of CR and TRE on aging biomarkers. Specifically, in the DiAL
Health study, which is being conducted at Pennington Biomedical (Baton Rouge, LA) and the University of
Alabama at Birmingham (Birmingham, AL), data will be collected from 90 adult individuals who are participating
in a 6-month randomized controlled trial. During the HALLO-P study, which is being conducted at Wake Forest
University Health Sciences (Winston-Salem, NC), 120 older adults will be enrolled in a 9-month randomized
controlled trial.