The Association Between Body Mass Index and Lymphoma Risk and Mortality: A Systematic Review and Dose–Response Meta-Analysis Publisher



Zamanian N ; Amiri Khosroshahi R ; Shadnoush M ; Tabaeifard R ; Ebrahimi Mousavi S ; Zahedi H ; Hajifathali A
Source: Critical Public Health Published:2026

Abstract

Introduction: Lymphoma is a common hematologic malignancy, and obesity may influence its development and prognosis, but evidence on the association between body mass index (BMI) and lymphoma outcomes remains inconsistent. This study systematically evaluated associations between BMI and lymphoma incidence and mortality. Theory: The study is based on evidence linking obesity-related metabolic dysfunction, chronic inflammation, hormonal changes, and immune dysregulation to cancer development and progression. BMI was used as a measure of adiposity. Method: PubMed, Web of Science, and Scopus were searched through May 2025 for prospective cohort studies assessing BMI and lymphoma outcomes. Two reviewers independently extracted data and evaluated study quality using ROBINS-I. Evidence certainty was assessed with GRADE. Random-effects models were used to calculate pooled relative risks (RRs) and hazard ratios (HRs) with 95% confidence intervals (CIs). Results: Thirty-two cohort studies including over 27 million participants were analyzed. Higher BMI was associated with increased lymphoma incidence (RR = 1.12; 95% CI 1.05–1.19) and mortality (HR = 1.32; 95% CI 1.18–1.47). Each 5 kg/m2 increase in BMI was associated with 5% higher incidence risk and 12% higher mortality risk. Stronger associations were observed for Hodgkin lymphoma and diffuse large B-cell lymphoma. Mortality subtype analyses, based on limited evidence, showed significant association only for non-Hodgkin lymphoma. Mortality analyses included 12 effect estimates from 7 cohorts and showed low heterogeneity (I2 = 10.5%). Discussion: Excess body weight is associated with increased lymphoma incidence and mortality. Further research is needed to clarify underlying mechanisms and evaluate weight-management interventions. © 2026 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.