Comparison between body mass index, triceps skin fold thickness and mid-arm muscle circumference in Saudi adolescents

Adolescence is an important period in an individualâs life. Overweight and obesity are fraught with several health problems even later in life. The objective of this study was to estimate the overweight, obesity, body fat and muscle content of Saudi adolescents as compared to a recognized reference population.

Data were collected from a sample of Saudi adolescents in Jeddah from 42 boys' and 42 girls' schools during the month of April 2000. Data collection was done by personal interviews to collect sociodemographic factors and by direct measurement of weight, height, triceps skin fold thickness (TSF) and mid-arm circumference (MAC). The 50th, 85th, and 95th percentiles (P50, P85 and P95) for body mass index (BMI) and triceps skin fold thickness (TSF) were taken, then the 50th, 90th, and 95th percentiles (P50, P90 and P95) for the mid-arm muscle circumference (MAMC) were calculated. These measurements were compared with corresponding values of the National Health and Nutrition Examination Survey I (NHANES I).

The P85 and P95 for BMI and TSF were higher for Saudi adolescents than the NHANES I and the difference was wider for P95. Conversely, there was a lower MAMC at P90 and P95 than the NHANES I reference population curves. The lower MAMC curves were less marked in girls than in boys. On the other hand, Saudi boys and girls showed on average similar body mass index indicated by BMI at P50, which was misleading, since those adolescents showing similar body mass index had more fatness than the average reference population indicated by TSF at P50, and less muscularity on average than reference population indicated by MAMC at P50.

Overweight and obesity with increased body fat content and decreased body muscle content appear to be widespread among Saudi adolescents even among those adolescents showing average body mass index. Public health interventions are required to improve quality of food, encourage physical activity and exercise, as well as correct the perception of appropriate body stature.