Bottle Feeding at Age 2 Raises Obesity Risk
Study Shows Link Between Childhood Obesity and Regular Bottle-Feeding by 2-Year-Olds
Weight Gain After Bottle-Feeding
For the study, which is published in the Journal of Pediatrics, researchers analyzed data collected in the Department of Education’s Early Childhood Longitudinal Study, Birth Cohort.
Children were included in the study at birth and assessed at 9 months, 24 months, 4 1/2 years, and 5 1/2 years.
Parents were asked, at the 24-month interview, if the child primarily drank from a bottle, a sippy cup, or a regular cup. They were also asked whether they usually put the child to bed with a bottle. If the answer to either question was yes, the child was considered to be a regular bottle user.
At age 5 1/2, children were weighed and measured. If their height and weight put them above the 95th percentile on standardized body mass index (BMI) charts, they were classified as obese.
Mothers were asked if they had ever breastfed and, if so, the age the child stopped breastfeeding. They were also asked what age solid foods were introduced.
Of the 6,750 children included in the study’s results, 17.6% were obese at age 5 1/2.
Nearly one in four (22.3%) was a regular bottle user at 24 months of age.
The prevalence of obesity at 5 1/2 years was about 23% in regular bottle users compared to about 16% in children who were not using a bottle.
After adjusting their data to account for 13 factors that are thought to influence the risk of obesity -- including socioeconomic status, race, maternal education, mom’s weight, breastfeeding, age at introduction of solid foods, and birth weight, 2-year-olds who were regular bottle users were about 33% more likely to be obese than those who primarily drank from cups at that age.
“This is a well-done study,” Bonuck says. “The main caveat, and this is a limitation of a large national survey, is that it is hard to say exactly what or how much of the daily calories came through the bottle.”
Bonuck points out that bottles come in all different sizes and can be filled to different levels, something this study wasn’t able to take into account.
The researchers acknowledge a number of other things that were missing. They didn’t have data on children’s physical activity, for example, or specific aspects of diet -- like total daily calories, sugar-sweetened beverages in the diet, or information on whether or for how long infants were exclusively fed breast milk.
Previous studies have suggested that exclusive breastfeeding for six months or more may reduce the risk of obesity later in life.