We’ve heard plenty of child obesity statistics in recent years — for example, the CDC says that obesity in kids has more than tripled since the 1980′s. But a large study published last week suggests that the problem may begin with babies as young as nine months old.
The researchers looked at data from almost 9,000 nine-month-olds and 7,500 two-year-olds from the Early Childhood Longitudinal Study-Birth Cohort — a nationally representative sample of kids born in 2001. They considered babies and toddlers between the 85th and 95th percentile to be “at risk”, and those over the 95th percentile to be obese (this is the CDC’s definition).
At nine months, 32% of babies were over the 85th percentile, and 34% were above that mark when they reached two.
There’s nothing more delicious than a chubby baby, and like me I’m sure lots of moms and dads bristle at the term obesity being applied to our littlest munchkins.
But here’s why we should pay attention to this study:
The measurements took into consideration both height and weight together — so a long healthy baby wouldn’t be lumped into the overweight category.
Of course it’s “normal” for a baby to be in the 95the percentile for weight — 5 percent of the population should be there, to be exact. But in this study, 17 percent were over the 95th. And likewise, 15 percent of the population should be over the 85th percentile, whereas the study found 32 percent to be there.
What are growth charts anyway? Well, the CDC’s height-weight charts are the most commonly used (and the ones used in this study as well). They don’t tell us what ideal heights and weights are, they describe the population at a given point in time. The most recent CDC charts are based on a large population of children across the country, mainly from the 1980′s and 90′s.
So according to this data, the number of heavy infants and toddlers has grown considerably in recent decades. And since childhood weight is related to adult weight, there’s no ignoring that a trend towards extra pounds could be starting earlier than preschool.
I have to add that the CDC charts aren’t considered the ideal chart for reference — the World Health Organization charts are the gold standard, because they’re based on a population of primarily breastfed infants. Even the CDC recommends using the WHO charts for children 0-2 years. Babies tend to measure higher on these charts compared to the CDC ones, because formula fed babies gain more weight on average after three months of age.
Just to head off an argument I hear every time this issue is raised: if your baby is in the 95 percentile it doesn’t mean it’s a problem (as I said, 5 percent were there at the time the charts were formed). The problem isn’t heavy babies, it’s the fact that there are more and more of them every year that matters.