Abstract Gender and ethnic trends were examined in 351 Mexican American and Anglo American children between the ages of four and seven. Four physiologic variables, seven observed and reported variables related to diet, and eight observed and reported variables related to physical activity were periodically assessed. Children were observed at home at meal times and at school (or a day care center) at lunch and recess. A linear regression model was used. Of the four physiologic variables, two variables (height and total skinfolds) showed significant ethnic differences, with Mexican American children showing greater skinfolds over time and the tendency to be shorter than Anglo American children. Of the variables related to diet, five of the seven variables showed gender or ethnic differences; percent of calories from fat and food preparation behaviors tended to place Mexican American children at greater risk. When examining physical activity, four of the eight variables showed gender and/or ethnic difference...