PRIMARY OBJECTIVE:~I. Determine the effect of a 3-month randomized dietary intervention with a probiotic kefir beverage in multiple myeloma (MM) patients on biomarkers of metabolism, and patient-reported pain and fatigue, gut health, and quality of life (QoL).~SECONDARY OBJECTIVE:~I. Determine the effect of kefir supplementation on gut microbial phylotype and predicted bacterial metabolic function, and assess associations with biomarkers of metabolism, and patient-reported pain and fatigue, gut health, and QoL.~EXPLORATORY OBJECTIVE:~I. Feasibility of a probiotic lifestyle intervention in MM patients.~OUTLINE: Patients are randomized to 1 of 2 arms.~ARM I: Patients consume commercial kefir beverage daily for 3 months.~ARM II: Patients maintain usual diet for 3 months.~After completion of study, patients are followed up at 30 days or until resolution of any study related toxicity.
This trial investigates the effect of fermented milk supplementation on symptoms of disease and treatment in patients with multiple myeloma. Patients with multiple myeloma may experience symptoms related to the disease and/or treatment that affect quality of life. Supplementing usual diet with a probiotic fermented milk product called kefir may contribute to reducing disease and treatment-related side effects through changing the intestinal bacteria community structure and related metabolism.