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

MVZ Leopoldina GmbH

Status: Completed

Conditions: Breast Cancer

Treatments: Behavioral: 5:2 intermittent fasting; Radiation: Curative radiotherapy

Study type: Interventional

Funder types: Other

Identifiers

NCT05861362

2022-01

Details and patient eligibility

About

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.

Full 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).

Enrollment: 13 patients

Sex: Female

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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13 participants in 1 patient group

FAST

Experimental group

Description:

5:2 intermittent fasting group

Treatment:

Behavioral: 5:2 intermittent fasting

Radiation: Curative radiotherapy