Time-Restricted Feeding Improves Metabolic Outcomes in Adults With Crohn’s Disease

Adults with Crohn’s disease (CD) who followed a time-restricted feeding (TRF) regimen for 12 weeks experienced significant improvements in body composition, clinical disease activity, and circulating adipokines compared with controls, according to a randomized controlled study published in Gastroenterology. The findings suggest that TRF may represent a feasible lifestyle intervention for addressing obesity-related metabolic dysfunction in patients with CD.

Study Findings

Obesity and overweight affect approximately 40% of individuals with CD, with visceral adiposity linked to systemic inflammation, reduced biologic response, poorer quality of life, and increased surgical risk. Although intermittent fasting has demonstrated metabolic benefits in the general population, this study represents the first controlled evaluation of TRF in patients with inflammatory bowel disease.

Investigators randomized 35 adults with CD in clinical remission and overweight or obesity to either TRF (n=20) or unrestricted eating (n=15). Participants in the intervention group fasted for 16 consecutive hours per day, 6 days per week, while consuming their habitual diet during an 8-hour eating window. Controls continued their usual eating pattern.

After 12 weeks, BMI decreased significantly in the TRF group compared with controls (Δ –0.9 ± 0.03 kg/m² vs +0.6 ± 0.3 kg/m²; P<.001). Energy intake and Mediterranean Diet Index scores remained similar between groups, suggesting that weight loss occurred independently of caloric restriction or diet quality. Mean adherence to the intervention reached 95% ± 8%.

Clinical disease activity also improved. Harvey–Bradshaw Index scores declined significantly in the TRF group (Δ –2 ± 4 vs –0.5 ± 2; P=.02), accompanied by a 40% reduction in stool frequency and a 50% reduction in abdominal discomfort compared with controls.

Metabolic biomarkers also improved. Serum concentrations of leptin, plasminogen activator inhibitor-1, and adipsin were all significantly reduced following TRF (P<.05), with leptin showing a marked decline (P<.001). Among participants with dual-energy x-ray absorptiometry measurements, visceral adipose tissue decreased in the TRF group while increasing in controls, resulting in a significant between-group difference (P<.05).

Within the TRF group, participants achieving more than a 1-unit reduction in BMI demonstrated correlations between greater weight loss and increases in both anti-inflammatory and proinflammatory cytokines. The investigators noted that this pattern may represent an evolving process of immune recalibration, although they described this interpretation as speculative. No between-group differences were observed in C-reactive protein or fecal calprotectin.

Clinical Implications

These findings suggest that TRF may offer benefits beyond weight reduction for overweight or obese adults with CD. Improvements in BMI, visceral adiposity, clinical symptoms, and adipokine profiles occurred without changes in reported energy intake or overall diet quality, supporting the possibility that meal timing itself may influence immunometabolic pathways.

For clinicians, the study highlights a potential nonpharmacologic strategy to address obesity-related metabolic dysfunction, an increasingly important consideration in CD management because excess visceral fat has been associated with poorer clinical outcomes and diminished response to biologic therapy.

However, the results should be interpreted within the context of a relatively small, 12-week trial involving patients in clinical remission. The absence of significant changes in C-reactive protein and fecal calprotectin indicates that larger, longer-term studies are needed to determine whether metabolic improvements translate into objective reductions in intestinal inflammation or improved long-term disease outcomes.

Expert Commentary

The study authors reported that the observed reductions in BMI, visceral adiposity, and adipokines "strengthen evidence that TRF improves adipose tissue distribution and metabolic health." Regarding cytokine findings, they cautioned that the simultaneous increases in anti-inflammatory and proinflammatory cytokines among participants with greater BMI loss are "speculative" but "may be compatible with an evolving process of immune recalibration."

The authors emphasized that no significant between-group differences were identified in C-reactive protein or fecal calprotectin after 12 weeks, underscoring the need for additional investigation.

Larger, longer-duration studies will be necessary to determine whether metabolic benefits translate into sustained improvements in inflammatory biomarkers and long-term disease outcomes.

Reference:

Haskey N, Ye  J, Lewis A, Yousuf  M, Reimer RA, Raman M. Time-restricted feeding reduces body mass index, visceral adiposity, systemic inflammation, and clinical disease activity in adults with Crohn’s disease: a randomized controlled study. Gastroenterology. 2026;170(5):1051-1054 DOI: 10.1053/j.gastro.2025.11.008 External Link