Abstract:
African American women are a ected by earlier onset of age-associated health deteriorations
and obesity disproportionally, but little is known about the mechanism linking body mass index
(BMI) and biological aging among this population. DNA methylation age acceleration (DNAm AA),
measuring the di erence betweenDNAmethylation age and chronological age, is a novel biomarker of
the biological aging process, and predicts aging-related disease outcomes. The present study estimated
cross-tissue DNA methylation age acceleration using saliva samples from 232 African American
mothers. Cross-sectional regression analyses were performed to assess the association of BMI with
DNAmAA. The average chronological age andDNAmethylation age were 31.67 years, and 28.79 years,
respectively. After adjusting for smoking, hypertension diagnosis history, and socioeconomic factors
(education, marital status, household income), a 1 kg/m2 increase in BMI is associated with 0.14 years
increment of DNAm AA (95% CI: (0.08, 0.21)). The conclusion: in African American women, high BMI
is independently associated with saliva-based DNA methylation age acceleration, after adjusting for
smoking, hypertension, and socioeconomic status. This finding supports that high BMI accelerates
biological aging, and plays a key role in age-related disease outcomes among African American women.
