Effect of Meal Timing During Adjuvant Treatment for Cancer

Effect of Meal Timing During Adjuvant Treatment for Cancer: A Randomized Clinical Trial

The goal of this clinical trial is to test meal-timing as a novel and sustainable interventional approach during cancer treatment to improve therapeutic response, patient well-being and long-term metabolic health. In alignment with these priorities, we propose to focus on patients with histologically or cytologically confirmed solid tumors treated with curative-intent surgical resection and planned initiation of systemic adjuvant therapy (chemotherapy, targeted therapy, immunotherapy, and/or radiation per standard of care).

A promising strategy for improving the efficacy of anticancer treatments and reducing associated toxicities involves combining treatment with fasting regimens. In pre-clinical and clinical studies, various forms of fasting have been shown to induce tumor regression and improve long-term survival. According to the differential stress sensitization theory, fasting is thought to sensitize tumor cells to the cytotoxic effects of chemotherapy and radiation, while protecting healthy cells by increasing stress resistance. While healthy cells slow their growth and become more stress resistant in response to fasting, cancer cells cannot survive in nutrient-deficient environments; although the underlying mechanisms are not fully understood. However, extended water-only fasting can be challenging for patients and poses undue health risks. Intermittent fasting, and specifically time-restricted eating (TRE), may offer a viable alternative. TRE involves eating within a shorter window (e.g., 8 hours) and fasting for the remainder of the day but involves no other dietary restrictions. Because of its simplicity, TRE may be more sustainable than other fasting regimens. TRE also improves several cardio-metabolic endpoints, including insulin sensitivity, which may also be beneficial during anticancer treatments.

Study Overview

• Status: Not yet recruiting
• Conditions: Cancer
• Intervention / Treatment: Other: Questionnaire Administration; Procedure: Biospecimen Collection; Behavioral: Time-restricted eating; Behavioral: Health coaching

Detailed Description

Participants will be randomized to one of two groups:

1. Time-restricted eating (TRE) (8-hour daily eating period, starting 1-3 hours after waking up), OR
2. A control group defined as a ≥12-hour daily eating period.

Participants are assigned to either TRE (8-hour daily eating period, starting 1-3 hours after waking up) or a control group defined as a ≥12-hour daily eating period. Their randomized meal assignment arm begins no later than 1-2 week after they begin cancer treatment and ends at end of treatment (resection if indicated). This is a period of approximately 6 months.

During this time, participants will be asked to record the time they started and finished eating every day. Electronic reminders and weekly calls to the participants will be made by study staff who maintain records of patient's meal timing. Researchers will time the TRE schedules relative to sleep time (not time of day), which is a reasonable proxy for circadian time. The control group was designed to mimic typical eating habits in the U.S., as data from NHANES suggest that the median American eats over a 12.5-hour period each day. Aside from these general prescriptions, no set number of snacks, meals, or calories will be prescribed. Instead, researchers will measure how TRE affects self-reported mealtimes, meal frequency, and food intake through a combination of daily adherence surveys, 3-day food records and continuous glucose monitoring (CGM).

Participants will receive weekly one-on-one nutrition counseling during the first month and then monthly counseling sessions thereafter. Participants will complete questionnaires at intake and subsequent follow-up assessments. Blood and stool samples will also be collected from participants throughout the study.

• Study Type: Interventional
• Enrollment (Estimated): 50
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jane Figueiredo, PhD; Phone Number: (310) 423-2746; Email: Jane.Figueiredo@cshs.org

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90048
      • Cedars Sinai Medical Center (CSMC)
      • Contact: Jane Figueiredo; Phone Number: (310) 423-2746; Email: Jane.Figueiredo@cshs.org
      • Principal Investigator: Jane Figueiredo, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥18 years (no upper age limit)
• Any sex or gender
• Histologically or cytologically confirmed solid tumor treated with curative-intent surgical resection and planned initiation of systemic adjuvant therapy (chemotherapy, targeted therapy, immunotherapy, and/or radiation per standard of care)
• BMI ≥18.5 kg/m2
• Willing and able to adhere to the assessments, visit schedules, prohibitions, and restrictions

Exclusion Criteria:

• No plan for systemic adjuvant therapy after surgery
• Strictly adhering to a <10-hour eating window on most days
• Regular overnight shift work (≥1 night shift per week)
• Dependent on parenteral or enteral nutrition
• Pregnant or breastfeeding
• Active second malignancy requiring systemic therapy (exceptions: non-melanoma skin cancers or in situ cervical cancers adequately treated)
• Severe psychiatric, cognitive, or social conditions that would interfere with adherence to study procedures

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Time-restricted eating (TRE); Participants assigned to the TRE group will have an 8-hour daily eating period, starting 1-3 hours after waking up [8 hours eating / 16 hours fasting per day (6+ days a week)].	Other: Questionnaire Administration; Complete questionnaire; Procedure: Biospecimen Collection; Undergo collection of blood and stool; Behavioral: Time-restricted eating; Participate in time-restricted eating plan; Behavioral: Health coaching; Receive nutrition counseling
Active Comparator: Control group; Participants assigned to the control group are not time-restricted, and have a 12+ hour window of eating per day.	Other: Questionnaire Administration; Complete questionnaire; Procedure: Biospecimen Collection; Undergo collection of blood and stool; Behavioral: Health coaching; Receive nutrition counseling

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient-reported treatment-related toxicities: Average weekly scores	Assessed via Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE v5) toxicities, which is administered weekly throughout intervention and therapy; average scores calculated at each time point, timed to oncologic treatment cycles.	Assessed weekly from start of intervention through end of intervention (up to approximately 6 months)
Treatment Delivery: Relative dose intensity (RDI)	Relative dose intensity (RDI), defined as delivered/planned dose intensity, will be analyzed both as a continuous outcome (% of delivered vs planned) and as a binary outcome (≥85% vs. < 85%). Regimen-level RDI will be calculated as the average across drugs or based on the dose-limiting agent.	At end of intervention (at approximately 6 months)
Treatment Delivery: Number of patients completing planned adjuvant therapy without unplanned dose reductions or delays		At end of intervention (at approximately 6 monhts)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinician-reported CTCAE grade ≥3 toxicities		Baseline through end of intervention (at approximately 6 months)
Clinician-reported Toxicity Index		Baseline through end of intervention (at approximately 6 months)
Changes in quality of life (QOL): EORTC QLQ-C30	Change in quality of life assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), a validated 30-item instrument measuring global health status/quality of life, functional domains (physical, role, emotional, cognitive, and social functioning), and symptom domains. Scores are linearly transformed to a 0-100 scale according to standard scoring guidelines. For global health status and functional scales, higher scores indicate better functioning or quality of life; for symptom scales, higher scores indicate greater symptom burden.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
PROMIS Anxiety	Change in anxiety measured using the Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety short form. Scores are standardized T-scores (mean = 50, standard deviation = 10). Higher scores indicate greater anxiety.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
PROMIS Fatigue	Change in fatigue measured using the Patient-Reported Outcomes Measurement Information System (PROMIS) Fatigue short form. Scores are standardized T-scores (mean = 50, standard deviation = 10). Higher scores indicate greater fatigue.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
PROMIS Physical Function	Change in physical function measured using the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function short form. Scores are standardized T-scores (mean = 50, standard deviation = 10). Higher scores indicate better physical function.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
UCLA Loneliness Scale	Change in perceived loneliness assessed using the UCLA Loneliness Scale. Scores are calculated by summing item responses, with higher scores indicating greater perceived loneliness.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Munich Chronotype Questionnaire (MCTQ)	Change in chronotype assessed using the Munich Chronotype Questionnaire. Chronotype is derived as mid-sleep time on free days, corrected for sleep debt (MSFsc), with later times indicating more evening preference.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Pittsburgh Sleep Quality Index (PSQI)	Change in sleep quality assessed using the Pittsburgh Sleep Quality Index (PSQI). The global score is calculated from seven components, with higher scores indicating poorer sleep quality.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Appetite Questionnaire	Change in appetite assessed using a validated appetite questionnaire. Scores reflect patient-reported appetite levels, with higher scores indicating greater appetite (or specify direction if opposite).	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Dutch Eating Behavior Questionnaire (DEBQ)	Change in eating behaviors assessed using the Dutch Eating Behavior Questionnaire (DEBQ), including emotional eating, external eating, and restrained eating subscales. Higher scores indicate greater endorsement of the respective eating behavior.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Fasting Insulin	Change in fasting insulin levels measured from blood samples	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Fasting Glucose	Change in fasting glucose levels measured from blood samples.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
IGF-1	Change in circulating IGF-1 levels measured from blood samples.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Total Cholesterol	Change in total cholesterol levels measured from blood samples.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
LDL Cholesterol	Change in low-density lipoprotein (LDL) cholesterol levels measured from blood samples.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
HDL Cholesterol	Change in high-density lipoprotein (HDL) cholesterol levels measured from blood samples.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Triglycerides	Change in triglyceride levels measured from blood samples.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
C-Reactive Protein (CRP)	Change in CRP levels measured from blood samples as a marker of systemic inflammation.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Vitamin D	Change in circulating 25-hydroxyvitamin D levels measured from blood samples.	Baseline (within 28 days prior to initiation of adjuvant therapy), approximately 2-3 months after treatment initiation, end of treatment (within 6 weeks after completion of adjuvant therapy), and follow-up (6-12 months after completion of treatment)
Changes in sleep and physical activity patterns measured by wrist actigraphy	Sleep and physical activity patterns will be assessed using wrist actigraphy to measure parameters such as sleep duration, sleep timing, sleep efficiency, and activity levels.	Baseline and end of treatment (approximately 6 months)
Change in gut microbiome composition and diversity from stool samples	Change in stool-derived gut microbiome composition, including relative abundance of microbial taxa, and microbial diversity indices (e.g., alpha diversity such as Shannon index), measured using sequencing-based methods (e.g., 16S rRNA sequencing and metagenomics).	Baseline, mid-treatment (approximately 3 months), and end of treatment (approximately 6 months)
Changes in glucose patterns measured using continuous glucose monitoring (CGM)	Glucose levels will be continuously monitored using a wearable continuous glucose monitor to assess changes in glycemic patterns associated with the intervention.	Baseline and end of treatment (approximately 6 months)

Collaborators and Investigators

• Sponsor: Fred Hutchinson Cancer Center
• Collaborators: National Cancer Institute (NCI); Cedars-Sinai Medical Center; Alaska Native Tribal Health Consortium; Alaska Native Medical Center
• Investigators: Principal Investigator: Jane Figueiredo, PhD, Cedars-Sinai Medical Center; Principal Investigator: Timothy Thomas, MD, Alaska Native Tribal Health Consortium (ANTHC)

Study record dates

Study Major Dates

• Study Start (Estimated): April 1, 2026
• Primary Completion (Estimated): August 31, 2029
• Study Completion (Estimated): August 31, 2029

Study Registration Dates

• First Submitted: March 6, 2026
• First Submitted That Met QC Criteria: April 6, 2026
• First Posted (Actual): April 13, 2026

Study Record Updates

• Last Update Posted (Actual): April 13, 2026
• Last Update Submitted That Met QC Criteria: April 6, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Time restricted eating; Time-restricted eating; Meal timing
• Additional Relevant MeSH Terms: Behavior; Feeding Behavior; Fasting; Neoplasms; Intermittent Fasting
• Other Study ID Numbers: RG1126131; 1P50CA285275-01A1 (U.S. NIH Grant/Contract); FHIRB21058 (Other Identifier: Fred Hutch/University of Washington Cancer Consortium)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No