Gene expression changes mediated by DNA methylation may play a role in pubertal tempo regulation, and availability ofmethyl donor nutrients affects these pathways. We examined first trimester maternal and adolescent diet patterns thatmay be associated with DNA methylation at long interspersed nucleotide (LINE-1) repetitive elements in adolescence usingleast absolute shrinkage and selection operator (LASSO) and calculated an ‘Epigenetics-Associated Diet Score’ (EADS) foreach pattern; then tested the associations of these scores with pubertal tempo among adolescent boys and girls. The ana-lytic sample included 118 boys and 132 girls aged 10–18 years. DNA methylation at LINE-1 repetitive elements was quanti-fied. Typical maternal and adolescent nutrient intakes were estimated using food frequency questionnaires. Interval-censored time to event and ordinal regression models were used to examine associations EADS scores with pubertal tempousing physician-assessed Tanner stages and self-reported menarche, respectively, adjusted for confounders. We observedassociations between maternal EADS and pubertal onset, but not pubertal progression. Each standard deviation (SD) greatermaternal EADS was associated with 52%higher odds of having later onset of menarche in both cross-sectional and prospec-tive analysis (P= 0.031 and 0.028, respectively). In contrast, we observed associations between adolescent EADS and puber-tal progression, but not pubertal onset. Among boys, for each SD higher adolescent EADS, there was 13%increase in odds ofslower genital progression (P= 0.050), as well as 26 and 27%increase in odds of slower left and right testicular develop-ment, respectively (P= 0.001). Epigenetic-associated diet influences pubertal tempo in a sex- and timing-specific manner.
