Selection of instrumental variables
According to the selection criteria, we included a total of 154 SNPs that are closely associated with telomere length, with all of them exhibiting a significance level below P < 5×10-8. Additionally, we calculated the F-statistic for each SNP, ranging from 29.9 to 1628.8, all of which exceeded 10. This indicates that these instrumental variables are unlikely to be influenced by instrument bias. The characteristics of these SNPs and the details of their association with telomere length, including p-values, beta coefficients, standard errors, effect alleles, and F-statistics, are presented in Table S2.