King’s College London scientists report that higher circulating theobromine levels are associated with a lower biological age in blood tests. The peer-reviewed analysis, published in Aging, combined data from 509 TwinsUK participants and 1,160 individuals from Germany’s KORA cohort. Biological age was assessed using DNA methylation measures and telomere-length estimates, both indicating a younger profile with more theobromine. The association appeared specific to theobromine after testing other cocoa and coffee metabolites, including caffeine. Authors caution this does not justify eating more chocolate and say mechanistic studies are underway to test causality and potential roles of polyphenols.