摘要Objective Telomere length is a key aging biomarker,but its sex-specific impact on individualized life expectancy remains uncertain.This study explores sex differences in leukocyte telomere length(LTL)and individualized expected years of life lost(YLL).Methods A prospective cohort of 445,399 participants(203,731 males and 241,668 females)from the UK Biobank was analyzed.LTL values were log-transformed,and YLL was calculated using life tables.Multiple linear regression was applied to examine sex-specific associations.Results In males,each standard deviation(S.D.)increase in LTL was linked to a 0.965-year decrease in YLL(95%CI:-1.025,-0.900;P<0.001).In females,longer LTL was related to a 0.102-year increase in YLL(95%CI:0.057,0.146;P<0.001).Among postmenopausal females,LTL showed a protective effect similar to that in males(0.387-year decrease,95%CI:-0.446,-0.328;P<0.001),while premenopausal females exhibited a detrimental association(0.705-year increase,95%CI:0.625,0.785;P<0.001).Comparable trends were observed across major aging-related diseases,pointing to a consistent biological pattern.Conclusion The influence of LTL on life expectancy varies significantly by sex,with protective associations seen in males and postmenopausal females.This suggests hormonal involvement in telomere dynamics.The results support integrating sex-specific perspectives into aging and telomere research and clinical practice.