~19 spots leftby Jun 2026

Intermittent Fasting for Breast Cancer Survivors with Obesity

Recruiting in Palo Alto (17 mi)
+1 other location
VC
Overseen byVictoria Catenacci, MD
Age: 18+
Sex: Any
Travel: May Be Covered
Time Reimbursement: Varies
Trial Phase: Academic
Recruiting
Sponsor: University of Colorado, Denver
Must be taking: Anti-endocrine therapy
Must not be taking: Anti-obesity drugs, Antipsychotics
Disqualifiers: ECOG status 2+, Diabetes, Cardiovascular disease, others
No Placebo Group

Trial Summary

What is the purpose of this trial?

This is a 3 month single arm pilot and feasibility study designed to examine the impact of an intermittent fasting lifestyle weight loss intervention on pre-specified clinical milestones (change in body weight, adherence to the fasting program, and moderate-to vigorous physical activity, MVPA) in adults with overweight and obesity and breast cancer after they have completed their cancer treatment. The investigators will also evaluate feasibility of recruitment and retention of study participants, safety of the intervention, and obtain feedback from participants to improve the program. Participants will receive a 3 month lifestyle weight loss program focusing on a 4:3 intermittent fasting paradigm (3 modified fast days per week) and support to increase physical activity to 150 minutes per week. Outcome measures will be assessed at the end of the 3 month intervention (primary endpoint) and after a 3 month weight maintenance follow up phase.

Will I have to stop taking my current medications?

The trial does not require participants to stop taking their current medications. However, you must not be using medications that significantly impact appetite, weight, or energy metabolism, except for anti-endocrine therapy for breast cancer and standard anti-nausea or anti-diarrhea medications.

What data supports the effectiveness of the treatment Intermittent Fasting for breast cancer survivors with obesity?

Research suggests that intermittent fasting during chemotherapy may help protect healthy cells and make cancer cells more vulnerable, potentially reducing chemotherapy side effects. It may also improve quality of life by reducing fatigue, nausea, and headaches, although the data is considered low quality and further studies are needed.12345

Is intermittent fasting safe for breast cancer survivors with obesity?

Intermittent fasting has been found to be generally safe for breast cancer patients, potentially reducing chemotherapy side effects like fatigue and nausea. However, more research is needed to confirm these findings and ensure safety for all individuals.12567

How is intermittent fasting different from other treatments for breast cancer survivors with obesity?

Intermittent fasting is unique because it involves specific eating patterns, like alternate-day fasting or time-restricted eating, rather than continuous calorie restriction. It may help protect healthy cells and make cancer cells more vulnerable during chemotherapy, potentially reducing side effects and improving quality of life.12348

Research Team

VC

Victoria Catenacci, MD

Principal Investigator

University of Colorado, Denver

Eligibility Criteria

This trial is for adults who have finished breast cancer treatment, are overweight or obese, and want to try a weight loss program. Participants should be willing to follow an intermittent fasting plan with 3 modified fast days per week and increase physical activity.

Inclusion Criteria

I am between 18 and 65 years old.
Live or work within 30 miles of the Anschutz Health and Wellness Center (AHWC) (exceptions may be made at the discretion of the Study PI on a case-by- case basis for highly motivated subjects)
Obtain a signed medical clearance from their oncologist for participation in the 4:3 IMF dietary intervention and BfitBwell clinical exercise oncology program. (If participants do not currently have an oncologist signed clearance form their PCP will suffice)
See 9 more

Exclusion Criteria

I have diabetes or high blood sugar, but it's well-controlled if I'm on specific medications.
History of clinically diagnosed eating disorders including anorexia nervosa, bulimia, binge eating disorder. Score >20 on the Eating Attitudes Test (EATS-26) or pattern of response on the Questionnaire of Eating and Weight Patterns (QEWP-5) suggestive of possible binge eating disorder or bulimia will require further assessment by the Study MD to determine if it is appropriate for the subject to participate in the study
Current severe depression or history of severe depression within the previous year, based on DSM-IV-TR criteria for Major Depressive Episode or history of other significant psychiatric illness (e.g., psychosis, schizophrenia, mania, bipolar disorder) which in the opinion of the Study PI would interfere with ability to participate in the diet and exercise interventions and provide feedback on the interventions via questionnaires and focus groups
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Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive a 3-month lifestyle weight loss program focusing on a 4:3 intermittent fasting paradigm and support to increase physical activity

3 months
Weekly check-ins (virtual or in-person)

Follow-up

Participants are monitored for weight maintenance and adherence to lifestyle changes

3 months
Monthly follow-up visits (virtual or in-person)

Treatment Details

Interventions

  • Intermittent Fasting (Behavioral Intervention)
Trial OverviewThe study tests a 16-week weight loss intervention using intermittent fasting (4:3 paradigm) combined with support for increasing exercise to at least 150 minutes weekly. It aims to see how this affects body weight and adherence among participants post-cancer treatment.
Participant Groups
1Treatment groups
Experimental Treatment
Group I: Behavioral Weight Loss Focused on Intermittent FastingExperimental Treatment1 Intervention
3-month integrated behavioral weight loss intervention with a dietary focus on intermittent fasting.

Find a Clinic Near You

Who Is Running the Clinical Trial?

University of Colorado, Denver

Lead Sponsor

Trials
1,842
Recruited
3,028,000+
Aviva Abosch profile image

Aviva Abosch

University of Colorado, Denver

Chief Medical Officer since 2019

MD

Uday B. Kompella profile image

Uday B. Kompella

University of Colorado, Denver

Chief Executive Officer since 2015

PhD in Pharmaceutical Sciences

National Cancer Institute (NCI)

Collaborator

Trials
14,080
Recruited
41,180,000+
Dr. Douglas R. Lowy profile image

Dr. Douglas R. Lowy

National Cancer Institute (NCI)

Chief Executive Officer since 2023

MD from New York University School of Medicine

Dr. Monica Bertagnolli profile image

Dr. Monica Bertagnolli

National Cancer Institute (NCI)

Chief Medical Officer since 2022

MD from Harvard Medical School

National Insitutes of Health

Collaborator

Trials
1
Recruited
40+

Findings from Research

Intermittent fasting (IF) during chemotherapy for breast cancer patients significantly reduced gastrointestinal toxicity compared to a non-fasting group, suggesting a protective effect of fasting against chemotherapy side effects.
The study, involving 48 HER2-negative breast cancer patients, also indicated that IF improved metabolic profiles, as evidenced by lower insulin levels in the IF group, which may enhance the overall efficacy of chemotherapy.
Intermittent fasting during adjuvant chemotherapy may promote differential stress resistance in breast cancer patients.Omar, EM., Omran, GA., Mustafa, MF., et al.[2022]
Intermittent fasting (IF) during chemotherapy for breast cancer patients was found to be feasible and safe, potentially alleviating chemotherapy-induced adverse effects like fatigue and nausea, although the quality of the data was low.
While IF showed some promise in reducing chemotherapy-induced DNA damage and improving glycemic regulation, the review did not find significant benefits on quality of life or tumor recurrence, indicating that more rigorous studies are needed to confirm these effects.
Intermittent Fasting in Breast Cancer: A Systematic Review and Critical Update of Available Studies.Anemoulis, M., Vlastos, A., Kachtsidis, V., et al.[2023]
Preliminary findings indicate that combining intermittent fasting or a fasting-mimicking diet with endocrine therapy may enhance the effectiveness of treatment for hormone receptor-positive breast cancer.
This combination approach could also help in reducing side effects associated with the endocrine therapy, suggesting a potential strategy for improving patient outcomes.
Fasting May Complement Endocrine Therapy.[2021]

References

Intermittent fasting during adjuvant chemotherapy may promote differential stress resistance in breast cancer patients. [2022]
Intermittent Fasting in Breast Cancer: A Systematic Review and Critical Update of Available Studies. [2023]
Fasting May Complement Endocrine Therapy. [2021]
Pilot study to assess prolonged overnight fasting in breast cancer survivors (longfast). [2022]
Fasting and weight-loss restrictive diet practices among 2,700 cancer survivors: results from the NutriNet-Santé cohort. [2019]
Alternate day fasting for weight loss in normal weight and overweight subjects: a randomized controlled trial. [2021]
Safety of alternate day fasting and effect on disordered eating behaviors. [2018]
Energy restriction and the prevention of breast cancer. [2013]