NEW YORK (Reuters Health) – Skinfold thickness during adolescence is a better predictor than body mass index (BMI) of high body fatness during adulthood, according to data from the Amsterdam Growth and Health Longitudinal Study.

The 168 men and 182 women who participated in the study provided 8 measurements of BMI and skinfold thickness between 1976 and 2000. Dr. Astrid C. Nooyens from VU University Medical Center, Amsterdam, and colleagues analyzed BMI and skinfold thickness during adolescence in relation to adult body fatness measured at a mean age of 37 years with dual-energy X-ray absorptiometry.

According to a report in the June issue of the American Journal of Clinical Nutrition, none of the boys and 1.7% of the girls were overweight at baseline, while 29% and 32%, respectively, had high body fatness as adults.

At the ages of 12 to 16 years, skinfold thickness was more strongly associated with adult body fatness than was BMI, Dr. Nooyens and colleagues report.

"Adolescents in the highest tertile of the sum of 4 skinfold thicknesses (S4SF) distribution had about 2 times the relative risk of becoming an adult with high body fatness, in comparison with adolescents in the highest tertile of the BMI distribution," they write. In boys aged 16 years, a higher BMI was not associated with a higher risk of becoming an overweight adult.

"As early as the age of 13 years, a difference in mean skinfold thickness was present between adolescents who did and did not become adults with high body fatness, which indicates that weight-gain prevention should start before adolescence," the authors also note.

Subscapular skinfold thickness was the best predictor of adult body fatness in adolescent boys, whereas biceps skinfold thickness was the best predictor in adolescent girls.

Dr. Nooyens and colleagues suggest that skinfold thickness "should be the preferred screening tool" to identify adolescents at increased risk of becoming overweight adults.

Am J Clin Nutr 2007;85:1533-1539.