Researchers from Temple University recommended that weaning them at the appropriate time might help reduce elevated obesity rates among U.S. youngsters. Instead of using the bottle to calm children, parents should instead address their underlying hunger and nutritional needs, they said.
Childhood development specialists say a child should generally be through with bottles by the age of 12 to 14 months. The Temple researchers said weaning by that age is "unlikely to cause harm and may prevent obesity along with other health problems." They said pediatricians, by giving such advice, could make a difference in the battle against childhood obesity.
"I agree that prolonged bottle feeding is likely another modifiable lifestyle risk factor for obesity in children," said Dr. Debra Bogen, an early childhood nutrition specialist at Children's Hospital of Pittsburgh, who was not involved in the study. "It may establish an eating pattern that encourages more frequent intake than is necessary." Bogen said the new findings gave her another reason, beyond tooth decay, "to encourage ending bottles no later than 15 months."
An 8-ounce bottle of whole milk contains 150 calories, or 12 percent of a healthy 2-year-old's daily dietary needs, the study authors wrote. When an additional bottle is given to a child who has met his or her daily calorie requirements, those extra calories can add up, the researchers reported in the current Journal of Pediatrics.
Dr. Robert Whitaker and Rachel Gooze of Temple's Center for Obesity Research and Education in Philadelphia worked with Sarah Anderson, an epidemiologist at the Ohio State University College of Public Health. They analyzed data from 6,750 Ohio participants in the Early Childhood Longitudinal Study, Birth Cohort, all born in 2001.
By the age of two, more than 1 in 5 of the children in the study (22 percent) still used a bottle for drinking or took a bottle to bed. When the youngsters were measured at age 5-1/2, almost 23 percent of the prolonged bottle users were obese, compared with just 16.1 percent of children weaned at a younger age. Obesity was defined as being in the 95th percentile or higher for height and weight among children of the same sex.
Prolonged bottle-users were 33 percent more likely to be obese at age 5-1/2, even when Whitaker and his fellow researchers accounted for such factors as their mother's weight, the child's birth weight, whether the child was breastfed, the age at which the child began eating solid food, and how much time the child spent in front of television or computer screens.
"If the bottle use is going on too long, it's serving a purpose for which it was never intended," said Keith Ayoob, a registered dietician and director of the nutrition clinic at the Rose R. Kennedy Center at the Albert Einstein College of Medicine. In some cases, he said, parents use the bottle to manipulate or control a child's behavior.
"Unfortunately that has consequences: they get in the habit of giving the bottle or giving food to manage children's behavior," he said. "It sets up a dynamic of the kids getting food for reasons that have much less to do with hunger or appetite than behavior issues." That, in turn, can lead to children having an unhealthy relationship with food, putting them at risk of the overeating that can drive obesity.
When parents come to him with children who continue to drink from a bottle beyond the age of 12 months, he asks, "'Can the child drink appropriately from a cup? If they can, there's no more need for the bottle. Certainly by age 2, it's time to stop, assuming the child has appropriate cup-drinking skills."
Prolonged use of a bottle can decay teeth, he said, particularly if parents are filling that bottle with juice or something "fruit-flavored and often sugary." The bottle also can become a meal substitute, "so that the kids are not eating. It can displace a balanced diet."
Ayoob said he has no problem with a child consuming two glasses of milk a day, because it's "a primary source of protein and a whole bunch of other nutrients." But after that, he said, "Let's get kids used to drinking water. Let's not feed anything excessively."
Bogen said that another way to keep kids from overconsuming calories as they're being weaned from bottles is to only allow them to drink from a bottle during meal time "while the toddler is sitting at the table/high chair" and to make sure they don't walk around with a bottle or sippy cup in hand. Bogen also said a sippy cup should not be "filled with juice or milk to have all day." Ideally, she said, toddlers "should be offered water between meals."
The study was funded by the U.S. Department of Agriculture's Food Assistance and Nutrition Research Program.