Primary objectives: The purposes of the study are to assess the growth status of urban Mexican children living in different geographic areas of the country, to estimate the prevalence of overweight and obesity, and to explore secular trends in body size.
Design: Cross-sectional surveys of 293 children 6-11 years from Sonora in the north-west of the country (155 boys, 138 girls), and 356 children 7-12 years from Veracruz on the Gulf Coast (194 boys, 162 girls) were undertaken in 1992 and 1993, respectively.
Procedures: Height and weight were measured; the body mass index (BMI, kg m(-2)) was calculated. Growth status was compared to USA reference data and to samples of Mexican children in 1926 and 1975. The prevalence of overweight (BMI > or = 85th and < 95th percentiles) and obesity (BMI > or = 95th percentile) was estimated.
Results: Girls and boys from Sonora and Veracruz do not differ in height, weight and the BMI. Mean heights are at (girls) or below (boys) the medians of USA growth charts, while mean weights are at (boys) or just below (girls) the 75th percentiles at most ages. As a result, mean BMIs are above (boys) and below (girls) the 75th percentiles over the age range studied. The prevalence of overweight and obesity is 40% in boys and 35% in girls, whereas the prevalence of obesity per se is 23% in boys and 17% in girls. Compared to urban Mexican children in the Federal District surveyed in 1926, children in the present sample are taller and heavier, but the secular trend in body weight is more pronounced since the mid-1960s. Heights of the current samples are similar to those of well-off children in Mexico City in the early 1970s, but weights are heavier.
Conclusions: The gap in height between well-off and lower socioeconomic status children in different regions of Mexico has been reduced, but there is an increase in the prevalence of overweight and obesity.