Copenhagen, Denmark - The US had the highest prevalence of overweight teenagers in a new 15-country study.1

Noting that obese teenagers are likely to become obese adults, and obesity in adults is known to increase the risk of cardiovascular diseases and diabetes, the authors conclude that teenagers represent an important group to reach through preventive programs addressing issues of diet and sedentary lifestyles.

One of authors, Dr Mary Overpeck (US Department of Health and Human Services, Rockville, MD) commented to heartwire that the US came out worst in this survey probably because teenagers there eat more fast foods and get less exercise than those in some European countries. "We have had access to fatty and prepared foods for more years here in the US, and the pace of life is faster, with more women working and so therefore more likely to use fast foods. We also use the car far more in the US than in Europe," she said.

Overpeck said that these patterns were very difficult to change and that there needs to be a concerted effort by multiple levels of government and community organizations to have an impact. "If current lifestyle patterns continue unchanged, there will be a massive rise in heart disease and diabetes in the US population," she noted.

The study, published in the January 2004 issue of the Archives of Pediatrics & Adolescent Medicine, used data from school-based surveys in 1997-1998 to calculate body mass indexes (BMIs) of 29242 boys and girls aged 13 to 15 years from Austria, the Czech Republic, Denmark, Flemish Belgium, Finland, France, Germany, Greece, Lithuania, Ireland, Israel, Portugal, Slovakia, Sweden, and the US.

The researchers point out that there are no agreed-on definitions of overweight in children and adolescents, which makes comparisons of prevalence across countries difficult. This analysis used BMI at the 85th to 94th percentile for age as a definition of "at risk for being overweight" and a BMI at or above the 95th percentile for age as the definition of "overweight." BMIs of 24.8 and 24.4 defined overweight (95th percentile) for boys and girls aged 13.5 years, respectively; BMIs of 26.0 and 25.4 indicated overweight for boys and girls aged 15.5, respectively.

Results showed that the US had the highest prevalence of overweight teenagers, with 12.6% of 13-year-old boys, 10.8% of 13-year-old girls, 13.9% of 15-year-old boys, and 15.1% of 15-year-old girls falling into this category. Other countries with high numbers of overweight teenagers were Ireland, Finland, and Greece.

Lithuania had the lowest prevalence of overweight teenagers1.8% of 13-year old boys, 2.6% of 13-year-old girls, 0.8% of 15-year-old boys, and 2.1% of 15-year-old girls. Other countries with low rates included the Czech Republic, Denmark, Flemish Belgium, France, Germany, and Sweden.

The authors note that to their knowledge no other studies are available with height and weight from so many countries, and as all countries performed the data collection within the same time span, this provides a strong basis for international comparison.