Prolonged bottle use tied to obesity

When to wean a child from the bottle can be a tricky call for parents, but new research appears to support a decision of sooner rather than later

Giving a baby or toddler a bottle as a snack or to lull them to sleep at night gives them liquid calories that can increase their risk of childhood obesity, a new study shows.

Children who were drinking from a bottle at two years of age were 1.33 times more likely to be obese at age 5½, researchers reported in Thursday's issue of the Journal of Pediatrics.

About 22 per cent of the 6,750 children in the U.S. study were still using a bottle to drink at the age of two or were usually put to bed with a bottle; either practice is considered prolonged bottle use.

Pediatricians generally advise parents and caregivers to start transitioning a baby from bottle to sippy cup between 12 months to 14 months of age.

Switching away from bottle

Study co-author Rachel Gooze, a doctoral student at the Center for Obesity Research and Education at Temple University in Philadelphia, suggested including the findings in part of the conversation between parents and pediatricians when babies are around six months to a year old.

"They could also include this in the discussion, and say ... additional amount of calories coming from the bottle might not be what your child needs for nourishment and nutrition; if it's a source of comfort or a routine, what are some other ways, strategies for transitioning away from that," Gooze said.

"It might be helpful for parents to think of moving from the bottle to a cup, much like they think about the transition from crawling to walking — so as a developmental milestone or something to celebrate."

Almost 23 per cent of the prolonged bottle users were obese by the time they reached 5½ years old, even after the researchers took into account other factors such as the mother's weight, education, smoking and the child's birth weight, screen-viewing time and breastfeeding.

'Food not a sedative'

A 24-month-old girl of average weight and length who is put to bed with a 250-millilitre (eight-ounce) bottle of whole milk would get about 12 per cent of her daily calories from that bottle, the researchers said.

Previous studies have also pointed to a link between prolonged bottle use and obesity. By following children from birth to age 5½, this is probably one of the best, said CBC's medical specialist Dr. Karl Kabasele.

Still, the authors cannot rule out if other factors besides bottle feeding could be contributing to obesity. For example, the parents could be giving excess calories in the rest of the diet beyond the bottle.

Leaving milk sugar in a child's mouth overnight is also a recipe for cavities, Kabasele said.

The other issue with bottle feeding is iron-deficiency anemia when milk displaces more iron-rich foods during a time when children are rapidly growing, he added.

Liquid calories tend not to have the same effect on satiety, or feeling full, as solid calories, said Dr. Arya Sharma, chair in obesity research and management at the University of Alberta.

It makes sense not to be drinking calories once a child starts eating, Sharma said.

"Food is not a narcotic, it is not a sedative … and here, you're using food to put someone to sleep. That's like taking a sleeping pill. You're using it as a narcotic. That's not a good use of food or calories. And that's not a good habit to get into in the first place."

The study was funded by the Economic Research Service, Food Assistance and Nutrition Research Program, U.S. Department of Agriculture.

With files from The Canadian Press