Subjects were studied retrospectively by history and prospectively in their natural setting for five years. A 2 x 2 x 5 multifactorial design was used where sex (males versus females) and weight (obese versus normal) were crossed with five different age groups according to decades (20-29, 30-39, 40-49, 50-59 and 60 or more years) respectively. A total of 50 (25 normal and 25 obese) were recruited for each age/sex group. Dependent variables included: weight, weight trends, fluctuation, body composition; diet; activity or exercise; weight maintenance behaviors and adaptive responses; general well-being, emotional states, psychopathology; routine blood and urinalyses; cardiovascular disease risk profile including lipids, blood pressure, sodium, potassium, calcium and phosphorus levels, diet, smoking, alcohol and caffeine use, onset of menopause and changes in medical status or medication use. Comprehensive assessment was done yearly.