Time-restricted eating may be beneficial to weight loss and cardiometabolic health improvement by regulating gut microbiota and serum metabolites, with early and late eating windows producing distinct microbial and metabolomic changes.
Key Findings
Results
6-h early TRE (7 a.m.–1 p.m.) increased abundance of Faecalibacterium and Lactobacillus and decreased abundance of unclassified_f_Peptostreptococcaceae compared to the control group.
Study design: 8-week randomized controlled trial with 60 young adults with overweight or obesity.
Three groups: 6-h eTRE (7 a.m.–1 p.m.), 6-h lTRE (12 p.m.–6 p.m.), and a control group (ad libitum).
Gut microbiota was analyzed by 16S ribosomal RNA (16S rRNA) sequencing.
All microbiota differences were statistically significant at p < 0.05.
Results
6-h late TRE (12 p.m.–6 p.m.) significantly increased abundance of Faecalibacterium and decreased abundance of Shigella compared to the control group.
Faecalibacterium was increased in both eTRE and lTRE groups, suggesting a shared microbial effect regardless of eating window timing.
Shigella reduction was specific to the lTRE group, indicating window-timing-specific microbial effects.
All differences were statistically significant at p < 0.05.
Gut microbiota analyzed by 16S rRNA sequencing.
Results
Differential serum metabolites were identified between eating window groups, with L-malic acid specific to eTRE and isovaleric acid specific to lTRE.
Serum metabolomics were quantified by liquid chromatography-mass spectrometry (LC-MS).
L-malic acid was identified as a differential metabolite in the eTRE group.
Isovaleric acid was identified as a differential metabolite in the lTRE group.
These metabolites were significantly associated with changes in weight, body fat, and systolic blood pressure (SBP) at p < 0.05.
Results
Differential serum metabolites from both TRE groups were significantly associated with changes in weight, body fat, and systolic blood pressure.
Associations were found between specific metabolites and cardiometabolic risk factors including weight, body fat, and SBP.
All reported associations were statistically significant at p < 0.05.
The findings suggest a gut microbiota–metabolite–cardiometabolic axis influenced by TRE.
The study population consisted of young adults with overweight or obesity over an 8-week intervention.
Results
The timing of the eating window during TRE produces distinct gut microbiota and metabolomic profiles, suggesting that early and late TRE exert partially different biological effects.
Both eTRE and lTRE shared the increase in Faecalibacterium, but differed in other microbial and metabolomic changes.
eTRE uniquely increased Lactobacillus and decreased unclassified_f_Peptostreptococcaceae; lTRE uniquely decreased Shigella.
Differential metabolites also differed by group: L-malic acid (eTRE) vs. isovaleric acid (lTRE).
The study was registered in the Chinese Clinical Trial Registry (ChiCTR2000039115).
What This Means
This research suggests that time-restricted eating (TRE) — limiting food intake to a 6-hour window each day — can change the types of bacteria living in the gut and alter certain chemicals in the blood, and that these changes are linked to improvements in body weight, body fat, and blood pressure. The study randomly assigned 60 young adults with overweight or obesity to one of three groups for 8 weeks: an early eating window (7 a.m. to 1 p.m.), a late eating window (noon to 6 p.m.), or an unrestricted eating control group. Both TRE groups showed increases in a beneficial gut bacterium called Faecalibacterium, but each window also produced its own unique microbial and blood chemical changes.
Specifically, the early TRE group also saw increases in Lactobacillus (another bacterium often considered beneficial) and a decrease in a potentially harmful bacterial family, while the late TRE group saw a decrease in Shigella, a bacterium associated with gastrointestinal illness. The blood chemical (metabolite) changes also differed by group — L-malic acid changed in the early TRE group and isovaleric acid in the late TRE group — and both were linked to improvements in weight, body fat, and systolic blood pressure.
This research suggests that the benefits of time-restricted eating for heart and metabolic health may work partly through changes in gut bacteria and blood metabolites, and that the timing of the eating window matters — early and late TRE are not identical in their biological effects. The findings highlight the gut microbiome as a potential pathway through which dietary timing influences cardiometabolic health, though further research in larger and more diverse populations over longer periods would help confirm these findings.
Zhang L, Wang Z, Zhang Z, Liu J, Li Z, Ren Y, et al.. (2026). Effects of Time-Restricted Eating on Gut Microbiota and Metabolites and Their Relationship With Cardiometabolic Risk Factors.. Obesity (Silver Spring, Md.). https://doi.org/10.1002/oby.70207