This meta-analysis aims to determine the effects of regular swimming on bone mineral density (BMD) in young adults (18-30 years). A systematic search was performed in Pubmed, SPORTDiscus and the Cochrane Library from the earliest possible year to March 2016. Swimmers were compared to non-athletic controls (CG) and to high-impact athletes (HIGH). Effect sizes with the Hedgesgin random effects models were developed. Fourteen studies met the inclusion criteria and were included in the meta-analyses. Swimmers presented similar BMD values to CG in whole-body (g=-0.20;P=0.251), femoral neck (g=-0.05;P=0.818) and lumbar spine (g=0.18;P=0.492); and lower BMD in the whole-body (g=-1.21;P<0.001), femoral neck (g=-1.51;P<0.001) and lumbar spine (g=-0.84;P=0.017) than the HIGH. For the whole-body differences, the higher the latitude the smaller the differences between swimmers and HIGH (B=0.10;P=0.001). For the femoral neck differences, age also seemed to reduce the differences between groups (B=0.19;P=0.020). Young adult swimmers present similar BMD values than CG and lower values than HIGH.