Effects of a Plant-Based High-Protein Diet on Fatigue in Breast Cancer Patients Undergoing Adjuvant Chemotherapy - a Randomized Controlled Trial.

Background: Breast cancer patients undergoing chemotherapy (CT) experience fatigue and other side-effects. Studies exploring interventions with a plant-based, high-protein diet on fatigue and body composition are lacking. The effects of these interventions on fatigue, body mass index (BMI), and body composition were evaluated.

Method: Newly diagnosed breast cancer patients who were scheduled for adjuvant CT ( = 103) were randomly assigned to the intervention or control group. Study outcomes included fatigue using fatigue symptom inventory and body composition using bioelectric impedance analyzer done at the start of CT, 3rd CT, and 3 weeks after CT. Linear mixed models were used to compare groups over time.

Results: Fatigue decreased from 57% to 28% in the intervention group and increased from 65% to 78% in the control group ( < 0.001). BMI decreased by 0.7 ± 0.8 kg/m2 in the intervention group, while the decrease was 0.4 ± 1.3 kg/m2 in the control group ( = 0.015). Fat mass decreased in the intervention group ( < 0.001) and muscle mass improved in the intervention group and decreased in the control group ( < 0.05).

Conclusions: A plant-based, high-protein diet during CT resulted in positive changes in fatigue, BMI and body composition.