In a study published in the journal Pediatrics, researchers from the University of Massachusetts and the Eunice Kennedy Shriver National Institute of Child Health and Human Development who tracked the medical records of 35,000 adolescents — 11 to 16 — found their health improved slightly over an eight-year period.
 

The researchers collected data on the youths' diets, level of physical activity, height, weight, and body mass index (BMI) between 2001 and 2009. The results showed that although the BMI of the participants increased over the full study period, it declined from 62.33 in 2005 to 62.07 in 2009.
 

Although most did  not engage in the 60 minutes of physical activity every day that experts recommend, the number of days in which that level was reached increased from 4.33 in 2001 to 4.53 in 2009. Meanwhile, fruit consumption increased from two to four days a week in 2001 to five to six in 2009, while vegetable intake increased from two to four days a week in 2001 to nearly five days in 2009.

The results also showed a drop in TV viewing time and consumption of sweets and sweetened beverages.
 

"These patterns suggest that public health efforts to improve the obesity-related behaviors of U.S. adolescents may be having some success," the researchers concluded. "However, alternative explanations for the increase in BMI over the same period need to be considered."