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Feasibility and Metabolic Effects of a 5:2 Fasting Intervention in Women With Breast Cancer During Radiotherapy

Not Applicable
Completed
Conditions
Breast Cancer
Interventions
Radiation: Curative radiotherapy
Registration Number
NCT05861362
Lead Sponsor
MVZ Leopoldina GmbH
Brief Summary

The intervention consists of the adoption of a 5:2 intermittent fasting diet during radiotherapy of breast cancer patients. The aim of the study was to assess the feasibility of this intervention and its impact on body composition and selected metabolic blood parameters.

Detailed Description

The 5:2 intermittent fasting (FAST) intervention consisted of two nonconsecutive days of fasting per week that could be chosen freely according to the patient's weekly schedule. The minimum amount of time to count as a fasting day was 24 hours, but patients were advised to aim for a complete fasting day including the nights before and after that day. On a fasting day, only water and unsweetened tea or coffee was allowed. However, given that fat is the macronutrient interfering the least with the metabolic adaptions to fasting, while carbohydrates disturb the most \[26\], patients were allowed to consume small amounts of bone broth/meat broth, coconut oil, butter/ghee or heavy cream as an "emergency plan", i.e., in case that they felt they needed some energy-containing foods to complete an initiated fasting day.

The primary study outcome was the feasibility of the FAST intervention and its effects on longitudinal body composition changes from baseline until the final week of radiotherapy (body mass, fat mass, fat-free mass, muscle mass, extracellular and total body water). Secondary endpoints were absolute changes in metabolic parameters, hormones, and overall quality of life scores in the FAST group. As a surrogate marker for insulin resistance, the triglyceride-glucose index (TyG) was calculated according to TyG=ln⁡(fasting triglycerides \[mg/dl\]×fasting glucose \[mg/dl\]/ 2).

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
13
Inclusion Criteria
  • Non-metastasized breast cancer
  • Indication for curative radiotherapy
Exclusion Criteria
  • metallic body parts that would interfere with electric bioimpedance (BIA) measurements
  • difficulties with understanding the aims of the study

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
FASTCurative radiotherapy5:2 intermittent fasting group
Primary Outcome Measures
NameTimeMethod
Dropout rate in the FAST intervention groupThrough study completion, an average of 5 weeks

Used to measure feasibility. The intervention is rated as feasible if dropout rate is \<30%

Longitudinal changes in body massThrough study completion, an average of 5 weeks

Body mass (in kg) is measured by a bioimpedance device with an integrated scale (seca mBCA, seca Deutschland, Hamburg, Germany).

Longitudinal changes in fat-free massThrough study completion, an average of 5 weeks

Fat-free mass (in kg) is estimated by a bioimpedance device with an integrated scale (seca mBCA, seca Deutschland, Hamburg, Germany).

Longitudinal changes in skeletal muscle massThrough study completion, an average of 5 weeks

Skeletal muscle mass (in kg) is estimated by a bioimpedance device with an integrated scale (seca mBCA, seca Deutschland, Hamburg, Germany).

Longitudinal changes in total body waterThrough study completion, an average of 5 weeks

Total body water content (in L) is estimated by a bioimpedance device with an integrated scale (seca mBCA, seca Deutschland, Hamburg, Germany).

Longitudinal changes in extracellular waterThrough study completion, an average of 5 weeks

Extracellular water (in L) is estimated by a bioimpedance device with an integrated scale (seca mBCA, seca Deutschland, Hamburg, Germany).

Secondary Outcome Measures
NameTimeMethod
Change between baseline and final (average 5 weeks) TyG indexThrough study completion, an average of 5 weeks

As a surrogate marker for insulin resistance, the triglyceride-glucose index (TyG) is calculated according to TyG=ln⁡(fasting triglycerides \[mg/dl\]×fasting glucose \[mg/dl\]/ 2)

Trial Locations

Locations (2)

Department of Radiotherapy and Radiation Oncology

🇩🇪

Schweinfurt, Bavaria, Germany

Leopoldina Hospital Schweinfurt, Department of Radiotherapy and Radiation Oncology

🇩🇪

Schweinfurt, Bavaria, Germany

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