36 beer mugs filled with milk

36 beer mugs filled with milk (Miguel Villagran, Getty Images)

NEW YORK (Reuters Health) - Two cups of cow's milk per day may be enough for most kids to have the recommended amount of vitamin D in their blood while maintaining a healthy iron level, suggests a new study.

"One of the common questions I get from parents when their kids become toddlers is, âhow much milk should they be drinking?' But we didn't have a good answer," said Dr. Jonathon Maguire, the study's lead author from Toronto's TARGet Kids! Collaboration.


The researchers write in the journal Pediatrics that previous studies showed cow's milk increases the amount of vitamin D in a child's blood while also reducing iron levels. Iron, which the body can get from meats and beans, is important for developing brains and protecting against anemia.


Maguire, a pediatrician at Toronto's St. Michael's Hospital, and his colleagues surveyed the parents of 1,311 children, who were between 2 and 5 years old and at pediatricians' offices in the Toronto area between December 2008 and December 2010. They also took blood samples from the children.

The researchers found one cup (250 milliliters) of milk was tied to a 5 nanomoles per liter (nmol/L) increase of vitamin D in the children's blood, and a small decrease in iron levels.


The researchers concluded that two glasses of cow's milk per day is enough to keep most kids at the suggested vitamin D levels while also maintaining a healthy amount of iron.


That's not a blanket suggestion for all children, however.



"I don't think there is too much cause for concern. I think this is probably old news for some parents," he said.

Patsy Brannon, a professor of nutritional sciences at Cornell University in Ithaca, New York, said the finding of 2 cups of milk is consistent with the U.S. Department of Agriculture's recommendation for two and three year olds, but said older children need 2.5 cups.




"There are other sources of vitamin D in the diet besides what comes from milk. We have to be concerned about excessive milk consumption in this age group," she said.
