Biological aging clocks tick faster in recent generations

Biological aging accelerates in younger generations, according to data from over 164,000 adults in the UK Biobank and the U.S. National Institutes of Health's All of Us program. Researchers measured systemic aging—across the entire body—using clinical biomarkers like PhenoAge and metabolic scores, finding that individuals born between 1990 and 1999 showed 92% of a standard deviation more biological aging than those born between 1965 and 1969, after controlling for chronological age. In the UK, the 1965-1974 cohort displayed a 23% increase compared to the 1950-1954 group. While rising obesity emerges as a leading suspect, researchers identify multiple mechanisms—from metabolic to systemic factors—operating in younger adults, territory still largely unmapped in conventional gerontology. For the longevity-conscious reader, the finding poses an uncomfortable question: if biological clocks now tick faster, what role do our present choices play in slowing that drift?