The study – which was led by UMass Boston researcher Ronald Iannotti at the Prevention Research Branch of the National Institute of Child Health and Human Development – concludes that, since the turn of the millenium, American middle- and high-schoolers have exchanged television watching for more regular exercise, while upping their fruit and vegetable intake.
[Iannotti] and co-author Jing Wang analyzed surveys given to a nationally-representative sample of students in sixth through tenth grades in 2001-2002, 2005-2006 and 2009-2010 as part of the Health Behavior in School-aged Children study. Each survey period included responses from between 9,000 and 15,000 adolescents.
The researchers found "encouraging" trends on measures of most diet and lifestyle habits.
For example, the number of days each week that kids reported being physically active for at least 60 minutes increased from 4.3 in 2001-2002 to 4.5 in 2009-2010, with similar trends among boys and girls. Likewise, youth reported eating breakfast on three school days each week on the first survey and 3.3 days on the last.
The average number of hours students spent watching TV each day fell from 3.1 to 2.4, with drops in both weekday and weekend viewing.
Frequency of fruit and vegetable consumption also rose slightly over time - although it remained at less than one daily serving of each, on average - and consumption of sweets and soft drinks fell.
While the proportion of survey participants designated as "overweight" or "obese" did not decrease, Iannotti still called the results of the investigaion "encouraging" – especially in light of other recent studies, which have reflected a similar trend among the nation's youth. He also notes that the physical benefits of children's behavioral choices may take some time to make themselves known.
Let's hope they do. While obesity rates have slowed or stabilized in other countries, obesity prevalence among American children has nearly tripled since 1980. A reversal in those figures – or even a leveling off, as Iannotti has observed – would be a much welcomed change of pace.