The Normative Aging Study (NAS) recruited 2280 Boston area healthy males aged 21 to 80 in 1961 through 1970. Clinical exams have continued at 3- to 5-year intervals. Obesity was not an exclusion criterion. Stability in weight and body habitus among 867 adult participants in the NAS was evaluated at 5- and 15-year follow-ups. At study entry, age was linearly related to central adiposity [abdominal circumference (AC) and ratio of AC/Hip Breadth (HB)] throughout the entire age range (30 to 78 years) and linearly and quadratically related to weight (WT) and Body Mass Index (BMI) (kg/m2) with maximal values at age 50. Over 15 years, changes in adiposity were strongly related to age; the greatest increases were among those initially 30 to 44 years of age with decrements in several adiposity measures (BMI, AC) only among the oldest subjects (60+ at entry); significant quadratic effects of age for BMI (p < .001), WT (p < .02) and AC (p < .01). There were major secular differences; men born later were heavier and fatter at the same ages as men born earlier. Men who gained (> 1 BMI) were younger while men who lost (> 1 BMI) had greater initial central adiposity than others. Smoking cessation was independently associated with increments in both central and peripheral adiposity. Moderate alcohol intake was associated with lower gains in AC/HB ratios at 15 years compared with little or high consumption. In general, aging was associated with trends towards central adiposity which tended to plateau or decrease at the oldest ages.