Growth, fatness, and leanness in Mexican-American children

Height, weight, arm circumference and the triceps skinfold were measured in 1269 Mexican-American school children, 6 through 17 years of age, from Brownsville, Texas. Arm circumference was corrected for the triceps skinfold to estimate midarm muscularity and fatness. The triceps skinfold was also used to estimate the occurrence of obesity and leanness. The heights and weights of Brownsville Mexican-American children compare favorably to those for Mexican-Americans in the Texas phase of th Ten State Nutrition Survey, and approximate the 25th centile of the United States Health Examination Survey (HES) reference data. Estimated midarm fat areas for Mexican-American children are similar to or slightly below HES values, while estimated midarm muscle areas are consistently below HES medians. The differences in estimated muscle mass of the arm reflect in part the smaller body size of Mexican-American children, and perhaps their diet, which tends to be adequate in calories and less satisfactory in protein. About 5 to 7% of the Mexican-American children are classified as "obese" using HES and TEcumseh (Michigan) criteria, both sets of reference data giving comparable results except in boys 14 to 17 years. However, about 30% of the Mexican-American children are classified as "lean" by the Tecumseh criteria and only 3% by the HES criteria. Estimates of obesity and leanness in a population thus vary with the criteria used.