The prevalence of obesity and underweight was estimated for residents of Missouri more than 9 years old on the basis of age, sex, household income, educational attainment, and population density from the results of a survey conducted in 1973. The incidence of overweight was greatest among children 10 to 16 years old and the least for adults 17 to 35 years old. Four percent of the girls 10 to 16 were greater than 159% of average weight for height. Among women greater than 59 years old the incidence of overweight and underweight were high. The proportion of adult women who were overweight as defined by average weight for height and body mass index (W/H2) was inversely related to household income and education. The same was true for adult men in relation to income but the reverse results were observed for education. A larger proportion of urban men were overweight as defined by body mass index compared to rural men. The incidence of obesity among males of all ages and females greater than 59 years old appeared to be related to residence in specific types of communities.