Time-restricted Eating (TRE) and Protein in Older Adults

The aim this study is to investigate the effects of time-restricted eating (TRE) on body composition, muscle function and markers of metabolic health of adults over 60 years old. This study will compare different variations of TRE - with and without an additional protein.

This study involves attending two study days at the University of Surrey for baseline and end-of-intervention measurement of body composition using a gold-standard dual energy x-ray absorptiometry (DEXA) scan; muscle function using hand grip strength and 30-second sit-to-stand tests; weight. A blood sample will be taken at each study visit to measure markers of lipid and glucose control, and insulin sensitivity.

Participants will be randomly allocated to one of four study groups:

* control group: maintain habitual dietary patterns * TRE group: fast for 16 hours overnight, eat between 12-8pm * TRE + Protein (AM): fast for 16 hours overnight, eat between 12-8pm; take a 30g plant-based protein supplement in the morning * TRE + Protein (PM): fast for 16 hours overnight, eat between 12-8pm; take a 30g plant-based protein supplement in the afternoon Participants will be asked to follow the intervention according to their allocated group for 8 weeks.