Chicago – Add babies to the growing ranks of overweight Americans.
In a new study, Harvard Medical School researchers document a 73.5 percent increase in fat babies over a 22-year period – a trend they warn has worrisome implications for the nation’s obesity epidemic.
“Even our very youngest children are gaining excess weight, not just adults and adolescents,” said Dr. Matthew Gillman, the study’s senior author.
Several factors are at play. More babies are large for their gestational age at birth than a quarter-century ago, in large part because more moms are entering pregnancy overweight and developing gestational diabetes while pregnant.
And more babies are gaining weight rapidly in the first few months of life.
The new numbers suggest “our obesity prevention efforts need to start at the earliest stages of human development,” said Gillman, associate professor of ambulatory care and prevention at Harvard.
That doesn’t mean parents should be putting babies with telltale rolls of fat on diets, doctors advised. But it does imply that moms and dads should be aware of how much food they’re giving infants and talk about nutritional concerns with their pediatricians.
The Harvard study tracked extremely chubby infants younger than 6 months.
Their weight adjusted for height placed them at or above the 95th percentile on growth charts, the cutoff point for being considered overweight. There is no definition of obesity in very young children.
By 2001, these babies accounted for 5.9 percent of infants, up from 3.4 percent in 1980, according to Gillman’s report, published in the July issue of Obesity, a medical journal. That translates into more than 242,000 babies of the 4.1 million born in the U.S. each year.
The Harvard study analyzed weight data for children up to 6 years old, but its most notable results have to do with very young infants.
Previous research has documented a sharp rise in the percentage of preschool children who are overweight but did not give results for only babies.
No one knows how many of these infants will shed extra weight as they begin to crawl and walk and as they grow older.
Some youngsters who start out on the top of the growth charts after birth will be of normal weight later in childhood, adolescence and adulthood.
But a relatively new body of research demonstrates that infants who gain weight rapidly early in life are at higher risk of becoming overweight in later childhood and adulthood.
Dr. Nicolas Stettler, assistant professor of pediatrics and epidemiology at Children’s Hospital of Philadelphia, has done groundbreaking work in this field.
“What we’ve shown is that if you look at weight gain early in life – during the first year, the first four months, even the first week – and then look at weight status in childhood and adulthood, you find a strong association,” he said.
Animal studies underscore the finding: They show that when rats are overfed, they’re more likely to become obese and diabetic.
“It could be that if you’re overfed early in life, that may affect the brain’s neurochemistry during a key development period and reprogram a person to eat to excess,” Stettler said.
Another hypothesis is that insulin secretion and metabolism could be altered in this early period.
