In summer, obesity rules

Season of video screens, snacks has children losing battle

Taina Pena, 9, of the South End worked out on an exercise machine at Body by Brandy fitness studio in Boston. (Erik Jacobs for The Boston Globe)

Ayanna Martinez, lean and lanky and savvy beyond her 13 years, knows the recipe for children gaining weight: summer vacation.

"Now they feel that school is over, all they want to do is watch TV or just lay back on the computer and eat," Ayanna said one recent afternoon while picking up nutrition pointers at a Dorchester tennis club. "It's like, 'No school! Video game city!' It's really very sad."

It is the paradox of summertime: The very months blessed with the greatest opportunity for running and jumping and playing have instead become prime time for packing on pounds. Once the plight of adults, obesity has become alarmingly common among the young, with children under 10 even being prescribed cholesterol-lowering pills. And specialists who treat overweight children say that the summer months are emerging as a leading suspect in the epidemic of childhood obesity.

Blame it on too much time in front of screens - computers, TV, and handheld-devices - and too little routine. Without the constancy of school and, even, the bland predictability of school lunches, summer looms as three months of unending temptation, fueled by advertising promoting sugar-laden snacks.

"You would think the summer would be a time when kids are really active and running around," said Julie Vanier, coordinator of Boston Medical Center's FANtastic Kids, the fitness and nutrition program that taught Ayanna about the importance of a good diet and exercise. "For many kids, it's the opposite. They have a lot of down time in the summer that they're trying to fill."

And there is reason to believe that this summer may be worse than most.

Weight specialists at Children's Hospital of Philadelphia, one of the nation's top pediatric medical centers, said they are seeing evidence that skyrocketing food prices and concerns about the safety of fruits and vegetables have made it harder to serve children healthy meals.

That is especially true, they said, for poorer families, who often disproportionately bear the burden of weight problems.

"Summer can be a very difficult time financially for families," said Lara Khouri, program director for the Healthy Weight Program at the Philadelphia hospital, which forged a partnership with a charity called Philabundance to collect healthy food staples for summertime dinner tables. "So this is a particularly interesting time to be thinking about the influences of this summer on obesity and kids."

Since the 1970s, the percentage of children overweight has tripled, according to the US Centers for Disease Control and Prevention. For instance, among youngsters ages 6 through 11, the rate climbed from 6.5 percent to 18.8 percent.

Schools - and the carbohydrate-rich breakfasts and lunches they often thrust in front of students - have frequently been implicated. "Schools," said Douglas B. Downey, an Ohio State University sociologist, "have been called obesity zones by some."

But Downey and colleagues at Indiana University weren't so sure. "We asked the question: When it comes to childhood obesity, are schools more part of the solution or more part of the problem?" Downey said.

The researchers calculated the body mass index - a standard measurement of size - for nearly 5,400 children, using data from a national survey. They found that during the summer between kindergarten and first grade, the youngsters' body mass index increased twice as fast as during the school year.

The rise, reported last year in the American Journal of Public Health, was especially steep for African-American and Hispanic children, as well as those already overweight at the start of kindergarten.

The lazy months of summer can also reverse progress achieved during the school year, according to a study from the University of Wisconsin. Their report in the Archives of Pediatrics & Adolescent Medicine last year found that when overweight middle-schoolers went on summer vacation, advances made during the school year in cardiovascular fitness, insulin levels, and body composition were negated, stolen apparently by summer's lack of discipline, specialists said.

"Families have agendas that are related to vacation and traveling, so it's very difficult for the child to adhere to" fitness programs, said Louisiana State University professor Melinda Sothern, a weight and nutrition specialist who pioneered a campaign called Trim Kids. "And then they're not on a good schedule at home because there are times when they are bored, and they have more access to the refrigerator because the parent is at work."

It wasn't always this way, of course. Dr. David Ludwig, director of the Optimal Weight for Life program at Children's Hospital Boston, said that in earlier generations, summertime heralded a period of increased activity for youngsters.

But hours consumed by instant messaging, video games, and TV - coupled with parents' fears about letting their children play outdoors - now keep kids sequestered inside even when the sun is shining. And among all forms of what's known as "screen time," Ludwig said, TV may be most insidious of all "because it affects both ends of the energy-balance equation.

"Clearly," he said, "when children are watching television, they're not at the beach or playing basketball in the back yard burning off calories. But also they're receiving an unending series of messages by way of commercials to eat the highest-calorie, lowest-quality food imaginable."

There was a starkly different message one recent evening as twilight fell on Dudley Square. Brandy K. Cruthird was putting children through their paces in her Brandy 4 Kidz gym. For summertime, she emphasizes fun and games: basketball, softball, hopscotch, jump rope, Hula Hoop.

"A lot of the kids today don't have the basic, fundamental games that we did," said Cruthird, a former college basketball player who trumpets the importance of fitness with the zeal of an evangelist. "We are really going to feel the effects that technology is having on our children in 10 years, and we're all going to pay a steep cost."

On this day, 9-year-old Taina Pena of the South End was there, her cherubic face twisting with determination as she pushed an exercise machine. Her mother and a healthcare worker recommended she join the gym, Taina said plainly, "because I weigh too much for my age."

Pam Seemore enrolled her two sons. One needs to shed some weight, the other doesn't.

"When they're in school, they have their breakfast, their lunch," said Seemore, who lives in Dorchester. "Summertime brings the ice cream, the smoothies, all the tempting stuff. This will help them resist that when they're adults."

Stephen Smith can be reached at stsmith@globe.com.