Efforts to increase healthy habits in American teens may be making an impact, according to a new study. Adolescents are moving more, eating better and watching less TV than they used to, and researchers say obesity rates in this group may finally be stabilizing.

The study results come a little more than a month after the Centers for Disease Control and Prevention announced it was seeing signs of progress in the fight against childhood obesity, especially in low-income families.

In the new study, published Monday in the journal Pediatrics, researchers analyzed data from three sets of students in grades 6 to 10. One set was surveyed during the 2001-2002 school year, another set during the 2005-2006 school year and the third set from the 2009-2010 school year. Researchers asked the students about their daily physical activity, nutrition, breakfast consumption, TV habits, and height and weight. They then compared the answers across the three school years to identify trends in healthy – or unhealthy – behaviors.

Overall, the results were encouraging. Between 2001-2002 and 2009-2010, researchers saw an increase in the number of days teens were getting at least 60 minutes of physical activity, and decreases in the amount of television they watched. The teens reported eating more fruits and vegetables and consuming fewer sweets, as well as drinking fewer sugar-sweetened beverages, such as soda. Researchers also saw an increase in the number of days the teens ate breakfast.

All great news, right?

Unfortunately, the researchers also saw significant increases in the teens’ body mass indexes, or BMIs, over the same time period. In 2001-2002, 10.3% of the students surveyed were obese; in 2009-2010, 12.7% were obese. A similar increase was seen in the overweight BMI category.

(Researchers noted that there was no significant increase in BMI between the 2005-2006 and 2009-2010 school years, indicating that the upward trend may have flat-lined in more recent years.)

The study also showed:

– BMI was higher in boys than girls, and higher in African-American and Hispanic youths compared to white teens

– Girls ate more fruits and vegetables than boys, but ate breakfast less often

– Girls were more likely to eat sweets; boys drank more sugar-sweetened beverages

– Older teens reported less daily physical activity, less vegetable/fruit consumption, more sweets and sugar-sweetened beverages and fewer breakfast meals than the younger study participants

While the increases seen in healthy behaviors are good, the researchers said, teens still aren’t meeting public health recommendations. Most of the adolescents surveyed did not get the recommended 60+ minutes of physical activity per day, nor did they consume more than five servings of fruits and vegetables every day. The majority also watched more than two hours of television daily, and consumed more sweets and soda than they should.

“There is considerable need for improvement,” the study authors concluded. More data is needed to confirm that obesity rates in this age group have actually stabilized, and more advances “may be necessary before the trend begins to turn downward.”