Kefir Is a Viable Exercise Recovery Beverage for Cancer Survivors Enrolled in a Structured Exercise Program

Med Sci Sports Exerc. 2021 Oct 1;53(10):2045-2053. doi: 10.1249/MSS.0000000000002690.


Purpose: This study investigated the effects of 12 wk of postexercise kefir consumption in cancer survivors who have undergone chemotherapy and/or radiation therapy.

Methods: All participants were enrolled in a structured exercise training program and separated into kefir (KEF) or control (CON) treatment groups. KEF consumed 8 oz. of kefir after exercise sessions (3 d·wk-1) for 12 wk. Outcome measures included assessments for body size and composition, aerobic fitness and muscular strength, medical history, and psychological state at pre- and postintervention time points. Blood was collected and analyzed for C-reactive protein (CRP), interleukin 6 (IL-6), and lipopolysaccharide (LPS) concentrations, and LPS-stimulated whole blood IL-6 and tumor necrosis factor α production were obtained using enzyme-linked immunosorbent assays at both time points. Monocyte numbers and phenotype were obtained using flow cytometry.

Results: Participants (N = 24; 9 males and 15 females) were an average of 61 ± 9.9 yr old. Kefir consumption was associated with 6.3% (P = 0.034) improvements in lean body mass, as well as 51.4% (P = 0.046), 39.3% (P = 0.017), and 64.7% (P = 0.021) improvements in measures of depression, fatigue, and gastric distress, respectively. KEF also experienced a significant 35.4% (P = 0.01) reduction in circulating LPS along with an 18.0% increase (P < 0.001) in classical monocytes % and a 22.3% decrease (P = 0.04) in nonclassical monocytes %. There were no significant changes in any other variables.

Conclusion: Twelve weeks of kefir consumption improved lean body mass, depression, fatigue, gastric distress, and a biomarker of gut dysbiosis. Kefir improved overall and classical monocyte numbers. Kefir should be considered as a component of a postexercise dietary regimen for cancer survivors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antineoplastic Agents / adverse effects
  • Biomarkers / blood
  • Blood Cell Count
  • Body Mass Index
  • Cancer Survivors* / psychology
  • Cardiorespiratory Fitness
  • Cytokines / blood
  • Depression / prevention & control
  • Exercise Therapy*
  • Fatigue / prevention & control
  • Female
  • Gastrointestinal Diseases / etiology
  • Gastrointestinal Diseases / prevention & control
  • Humans
  • Inflammation / prevention & control
  • Kefir*
  • Male
  • Middle Aged
  • Monocytes / metabolism
  • Muscle Strength
  • Quality of Life
  • Radiotherapy / adverse effects


  • Antineoplastic Agents
  • Biomarkers
  • Cytokines