When it is time to wean your baby off the bottle? This can be difficult for new parents to gauge, but a new study encourages families not to wait too long.
The American Academy of Pediatrics recommends that babies give up the bottle entirely by about age 1, and no later than 18 months. But the new study, an analysis of data on 6,750 children born in 2001, who participated in the Early Childhood Longitudinal Study, Birth Cohort, found that 22% of babies were still using bottles regularly at 24 months. And nearly a quarter of those children, the study found, were obese by age five-and-a-half.
By comparison, 16% of children who had stopped using bottles by age 2 were obese three-and-a-half years later.
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The researchers suggest that “prolonged bottle use” — drinking from the bottle beyond 12 to 14 months — adds excess calories to a child’s diet, increasing the risk of weight gain. Kids start eating solid foods around four to six months; by age 1, the typical baby is mainly eating solid food, supplemented with about 10 to 16 ounces of whole milk per day (and, for some children, breast-feeding).
But if toddlers continue to take bottles on top of that (an 8-ounce bottle of milk contains 150 calories, or 12% of what a healthy 2-year-old needs each day), the calories start adding up.
The authors of the study accounted for other factors that could also influence child obesity, including maternal health and obesity, socioeconomic status, whether kids were breast-fed as infants and the age at which kids began eating solid foods.
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Even after controlling for those factors, two-year-olds who drank from the bottle were still more likely to be obese — defined as having a body mass index at or above the 95th percentile for their age — than kids who were weaned earlier, the researchers say.
They add that relying on bottles regularly at mealtime or putting a child to bed with a bottle isn’t just a concern for obesity. These behaviors may also increase the risk of iron deficiency, if kids aren’t getting enough nutrients from solid foods, or promote tooth decay when kids take bottles to sleep and fail to engage in proper oral care.
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The authors encourage parents to discuss weaning strategies with their pediatricians, if they’re having trouble. “We definitely recognize stopping the bottle at a year of age is not easy, and stopping it at 2 years of age may be even harder,” lead author Rachel Gooze, a Ph.D. student in public health at Temple University’s Center for Obesity Research and Education, told HealthDay. “It might be helpful to think of moving from a bottle to a cup as a developmental milestone, like moving from crawling to walking, which is something to celebrate, even if it has challenges.”
The study was published in The Journal of Pediatrics.