Results from a large study on kids and weight drew an understandable response from Nancy Gruver:

"Hallelujah!"

The study, the most recent findings from Project EAT, a long-term research project on kids and their eating habits at the University of Minnesota, suggests that many girls finally are rejecting the message that thin is the only available dress size.

While no one is suggesting that the battle of the bulge is over for American kids, or certainly for American adults, the findings "are really promising," said lead researcher Dianne Neumark-Sztainer, a professor in the U's division of epidemiology and community health.

For girls, anyway. More on boys in a minute.

Neumark-Sztainer and colleagues took a look at the weight and eating habits of more than 3,000 Minneapolis and St. Paul middle school and high school students in 1999, and another 2,800 students in 2010. Trends among girls were encouraging.

Their weight did not significantly increase over time, perceptions of overweight status were more accurate and the use of healthy eating habits remained high.

In addition, dieting among girls decreased by 6.7 percent, unhealthy weight-control behaviors decreased by 8.2 percent and extreme weight-control behaviors decreased by 4.5 percent.

"Maybe the message has gotten through, to some extent, that we need to change the conversation we're having with our daughters," Neumark-Sztainer said.

Gruver, of the "hallelujah," has been key to that conversation. Twenty years ago, she and her husband, Joe Kelly, founded Minnesota-based New Moon Girls, a magazine and website that offers 50,000 girls "a place to be listened to and encouraged to say their truth," she said.

While still aware that "appearance is how girls are frequently judged," Gruver said the EAT study "is an indication that girls are growing more aware that these messages are there to sell products and are not messages about them. That is something we, and so many other people, have been working on for so long," she said.

"I'm very excited and encouraged."

So back to our boys. Not as encouraging, particularly if those boys are members of minority groups.

Neumark-Sztainer found that obesity rates among boys increased by 7.8 percent from 1999 to 2010, with large ethnic and racial disparities. In black boys, for example, the prevalence of obesity increased from 14.4 percent to 21.5 percent. Among Hispanic boys, obesity rates jumped from 19.7 percent to 33.6 percent.

A Minnesota Department of Health (MDH) report drew similar conclusions around gender. It found that 12 percent of ninth-grade boys and 13 percent of 12th-grade boys are obese, compared with 6 percent for girls in each age group.

Obvious theories come to mind, including a propensity among boys to consume junk food and trendy sports drinks, which are full of sugar. Some community sports programs, once free, are no longer. And boys, who once roamed free for hours, now sit in front of computer screens as their female peers take to soccer fields and basketball courts.

"It used to be that boys were more active than girls," said Chris Kimber, MDH supervisor for physical activity and nutrition. "But all the technology could be having quite a negative impact on their activity levels."

The assumption that boys don't care about being overweight is largely untrue. "Boys are sensitive about their appearance," said Eileen Crespo, a pediatrician at Hennepin County Medical Center.

That means choosing our message to them carefully, just as we do with girls. The EAT study found that the best way to avoid food problems is to focus on healthful eating instead of bodies and weight.

It's a strategy Crespo embraces. "I tell boys, 'We're not trying to make you skinny. We want to make you healthy.' " She often teams up with teen boys to create a plan to walk to the park or on a treadmill or do Zumba via YouTube with their parents.

"Sometimes, we can stabilize their weight gain as they grow into those excessive pounds."

Crespo's greatest challenge, though, is battling the stubborn cultural and economic divide, which the EAT study highlights. Riding your bike to the park is a great idea, if you live in a neighborhood with a safe park. Picking up vegetables and fruit is essential to a healthy lifestyle. But what if you live nowhere near a major grocery store or are surviving on a limited income?

That's why efforts including the Statewide Health Improvement Program (SHIP) are increasingly important. One effort, for example, is a collaboration between the St. Paul Public Schools and African-American churches to encourage healthy eating and increased physical activity.

"The work hasn't focused on boys in particular, but rather the whole populations reached by those institutions," said Ramsey County SHIP coordinator Julie Seiber.

It's a lot to bite off, but it's essential if we are to stem this troubling trend. Crespo agrees.

"In our populations, we have such huge numbers of overweight kids. We have no gender divide yet."

gail.rosenblum@startribune.com

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