Science2013-2023United Stateshigh confidence

Among US young adults aged 18–34, chronic-condition prevalence increased from 52.5% in 2013 to 59.5% in 2023, and multiple chronic condition prevalence increased from 21.8% to 27.1% over the same period.

Notes on verification

Verbatim statistic from CDC BRFSS-based study published in Preventing Chronic Disease (2025), corroborated by PubMed and PMC full text with matching figures; no contradicting data found. [tier=silver indep_score=0.925 clusters=2 claim_tier=notable]

Sources