Obesity battle starts young for urban poor

By the time they reach the age of 3, more than one-third of low-income urban children are already overweight or obese, according to a study released yesterday that provides alarming evidence that the nation's battle of the bulge begins when toddlers are barely out of diapers.

Researchers armed with scales and measuring devices visited nearly 2,000 families in 20 US cities, including Boston, and evaluated the weight and height of 3-year-olds in an unprecedented effort to focus on obesity among the nation's most vulnerable children.

Their finding: 35 percent of the low-income 3-year-olds were overweight or obese, a result more than twice the national rate for obesity among preschool children of all income levels and racial groups. Low-income Hispanic children, the researchers reported in the on line version of the American Journal of Public Health , were the most likely of all to have a weight problem, with 44 percent of those toddlers overweight or obese.

In Boston, where children were found to be slightly less heavy than the 20-city average, health officials yesterday announced they are giving $279,000 to community groups committed to joining the war on obesity, taking the fight directly to the city's streets, schools, and even urban farms. The money will fund outreach campaigns for the young and people of color, such as promoting health through dance and hip-hop music.

"We know that many of the habits that people retain for the rest of their life are established in childhood, so it's a critical period to educate folks about what they can do," said John Auerbach, executive director of the Boston Public Health Commission .

Specialists in pediatric nutrition said the new findings mirror what they witness in their own practices, as the waistlines of even the youngest patients have expanded at a troubling rate. The medical consequences can be significant, physicians said, with toddlers suffering from sleep apnea and misshapen limbs as a result of their weight. In addition, overweight toddlers are at risk of growing up to be overweight, with the attendant constellation of health woes, including diabetes, heart disease, and cancer.

It is a health crisis, the specialists said, fueled by eating too much calorie-laden processed food and drinking too many sweetened beverages while also spending more hours plopped in front of television and computer screens than earlier generations.

But toddlers' weight problems are also a legacy of the obesity epidemic among adults: Overweight mothers tend to give birth to bigger babies who are exposed to insulin imbalances while in the womb that can predispose them to obesity.

"The whole country is struggling with this," said Virginia Chomitz , senior scientist at the Institute for Community Health at the Cambridge Health Alliance . "There's a lot of factors in our environment and our lifestyle that are pushing us toward being fatter. It's an uphill battle to push against that tide."

Pediatricians have watched with concern as children have grown plumper. Since 1971, the share of children nationally who are overweight has doubled, a trend specialists expect will continue. But Rachel Tolbert Kimbro , a researcher at the University of Wisconsin-Madison, as well as scientists from Columbia and Princeton universities, wanted to look at the group that disproportionately bears the burden of obesity: the underprivileged.

Their study, underwritten by federal agencies and private foundations, focused on a group recognized to be especially vulnerable to obesity, the children of urban low-income parents, defined in part as those families receiving federal aid to help buy food for children and their mothers.

"There are so few studies that look at kids this young that we really don't know what trends look like for children who are at age 3 -- we don't know how many 3-year-olds were obese or overweight 10 years ago," Kimbro said. "But there's definitely a sense that this is a new problem, that we're seeing children this young not only overweight and obese but also with the attendant health problems."

Determining whether an adult is overweight is fairly straightforward, but measuring it among children must take into account that they are growing, and not always at the same rate. During certain periods, for instance, girls are expected to weigh more than boys of the same age.

The new study relied on the growth charts developed by the federal government that are a staple of pediatricians' offices. The authors defined as overweight children weighing more than 85 percent of those in their age group. Children weighing in excess of 95 percent of their peers were declared obese.

Using those standards, a 3-year-old girl standing a bit more than 3 feet tall would be considered overweight if she weighed nearly 39 pounds -- 4 pounds above average -- while an obese girl would weigh more than 46 pounds.

In the 20-city analysis, which included cities from Boston to San Jose, Calif., 17 percent of the low-income toddlers fit into the overweight category while 18 percent were categorized as obese. In Boston, 14 percent were overweight and 14 percent were obese.

"Some of the factors that made those young children be overweight at that young age are going to remain there until they become adolescents," said Dr. Nicolas Stettler , a pediatric nutrition specialist at Children's Hospital of Philadelphia .

Doctors at Boston Medical Center , the city hospital that treats the most low-income patients, regularly see the toll exacted by weight on toddlers. Records on children between the ages of 2 and 5 at the hospital show that 39 percent of the Hispanic patients were overweight or obese, said Dr. Carine Lenders , director of Boston Medical's Nutrition & Fitness for Life Program.

Low-income parents often tell Boston Medical Center doctors that fresh fruits and vegetables either aren't accessible in the inner city or cost too much, Lenders said. "And a second issue is the safety in their area," which sometimes limits children's physical activity, she said. "A lot of parents don't feel their kids are safe on the streets, so they keep them in the house, and the best baby sitter in the house is the TV."

Authors of the study said they were troubled by the disparity in weight trends between Hispanic toddlers and the white and African-American children, but could find no clear evidence to explain the difference.

Margarita Alegría , who specializes in the study of healthcare disparities at Cambridge Health Alliance , suggested that some of the difference may be attributable to varying cultural perceptions of what constitutes a healthy baby. Among Hispanics, she said, there may be a tendency to equate chubbiness with health.

Like other specialists, Alegría said all parents should be told about the importance of a healthy diet and active lifestyle for their children. After all, specialists said, no doctor is suggesting that a 3-year-old be placed on a specific weight-loss diet.

"Sometimes," Alegría said, "it's not only saying what women should be doing but also showing how to problem solve, how to access those nutritious foods, and helping them make choices about what is healthy eating and how to read a food label."

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