Perspective:Time-RestrictedEating—Integrating theWhatwiththeWhen

Abstract

Time-restrictedeating(TRE)isapopulardietarystrategythatemphasizesthetimingofmealsinalignmentwithdiurnalcircadianrhythms,permitting adlibitumenergyintakeduringarestricted(∼8–10h)eatingwindoweachday.Unlikeenergy-restricteddietsorintermittentfastinginterventions thatfocusonweightloss,manyofthehealth-relatedbenefitsofTREareindependentofreductionsinbodyweight.However,TREresearchtodate has largely ignored what food is consumed (i.e., macronutrient composition and energy density), overlooking a plethora of past epidemiological andinterventionaldietaryresearch.TodeterminesomeofthepotentialmechanismsunderpinningthebenefitsofTREonmetabolichealth,future studiesneedtoincreasetherigorofdietarydatacollected,assessed,andreportedtoensureaconsistentandstandardizedapproachinTREresearch. ThisPerspectivearticleprovidesanoverviewofstudiesinvestigatingTREinterventionsinhumansandconsidersdietaryintake(bothwhatandwhen foodiseaten)andtheirimpactonselectedhealthoutcomes(i.e.,weightloss,glycemiccontrol).Integratingexistingdietaryknowledgeaboutwhat foodis eaten withour recent understanding onwhen foodshouldbe consumedisessential to optimizethe impact of dietarystrategies aimed at improvingmetabolichealthoutcomes.