The Impact of Time-Restricted Eating on Diet Quality in Humans: A Systematic Review

Time-restricted eating (TRE) is a chrono-nutrition approach that limits daily food intake to a consistent window of time. Although many studies have explored the effects of TRE on weight, glycemic control, and other metabolic markers, the impact of TRE on overall diet quality remains unclear.

To evaluate the effect of TRE on diet quality outcomes in humans.

A structured search was conducted across 4 electronic databases (PubMed, Embase, CINAHL, and Web of Science) until April 2025 and following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Two researchers independently conducted the screening and selection of articles. Data extraction from eligible studies was performed by 1 researcher.

Five studies met the inclusion criteria (n = 184 participants), all of which were variations of randomized trials. Three studies reported modest improvements in diet quality scores, though only 1 reached statistical significance. Flexibility in choosing eating windows, higher baseline body mass index, and provided nutrition support emerged as potential moderators of positive change. However, most studies were small, short term, and varied in intervention design and assessment tools. Furthermore, the presence of co-interventions such as energy restriction or nutrition education likely confounded outcomes.

Although TRE alone has shown inconsistent effects on diet quality, studies incorporating behavioral support or nutrition guidance resulted in more favorable outcomes. Future research should prioritize standardized methodologies to assess diet quality and explore TRE combined with dietary advice to fully understand the potential of TRE to support sustainable dietary improvements and long-term health outcomes.

PROSPERO registration No. CRD420251048396.