Dietary restriction (DR) is the only intervention that has been shown to increase average and median life span in laboratory rodents. The effect of long-term, moderate DR on body composition and fat distribution was evaluated in male rhesus monkeys. Thirty animals (8-14 years of age)fed either 30% less than baseline intake (R, n = 15) or allowed to eat to satiety (C, n = 15), have been assessed semiannually using somatometrics and dual-energy alpha-ray absorptiometry (DXA)for 7.5 years. R subjects have reduced body weight (p <.0001), total body fat (p < .0001), and percentage body fat located in the abdominal region (p < .05). In addition, there has been a sustained reduction in plasma leptin concentrations (p <.001). These findings suggest reduced risk for common morbidities, such as insulin resistance, dyslipidemia, and type 2 diabetes mellitus, that are associated with advancing age and increased levels of bodyfat, especially in the visceral depot.