Kids Who Drink Non-Cow’s Milk Are Shorter Than Peers

Children who regularly consume plant-based milk or other non-cow’s milk products are smaller than their peers who drink old-fashioned cow’s milk, suggests a new study.

Each daily cup of non-cow’s milk that children consume is associated with a smaller height, report a group of researchers from St. Michael’s Hospital in Toronto in the American Journal of Clinical Nutrition. By age 3, children who drank three cups of non-cow’s milk were more than a half inch shorter on average than their milk-drinking counterparts.

One of the surprising results of the study was that the volume of non-cow’s milk that one consumed was directly tied to a lower height — that is, the more non-cow’s milk a child drank, the shorter they were.

For each cup of non-cow’s milk consumed, a child was 0.4 centimeters, or about 0.2 inches, shorter than those who consumed cow’s milk.

“It’s not like if you’re not consuming cow’s milk, you’re a little shorter,” Dr. Jonathon Maguire, a pediatrician at St. Michael’s Hospital, told CNN Health. “It’s more like if you are consuming non-cow’s milk, with each cup that a child consumes, that child on average appears to be a little bit smaller, a little shorter. That’s a bit surprising.”

The study authors surmise that the nutritional content of cow’s milk, which is heavy on protein and fat, may be contributing significantly to a child’s growth and development. Other milk beverages, such as almond milk, may not be giving kids the same boost.

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“The nutritional content of cow’s milk is regulated in the United States and Canada, while the nutritional contents of most non-cow’s milks are not,” said Maguire. “The lack of regulation means the nutritional content varies widely from one non-cow’s milk product to the next, particularly in the amount of protein and fat.”

Maguire adds that the nutritional value of some milk-like products may need further attention.

“If products are being marketed as being equivalent to cow’s milk, as a consumer and a parent, I would like to know that they are in fact the same in terms of their effect on children’s growth,” he said.

While the study authors use height as a metric of overall health, that measuring stick doesn’t appear as strong to other medical professionals not involved in the study.

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“Taller children and heavier children are not necessarily healthier adults, or even healthier children,” Amy Joy Lanou, a professor of Health and Wellness at the University of North Carolina-Asheville, told CNN Health. “I think they’re using height as a marker for health, and I’m not sure that’s appropriate.”

Other experts warned that reading too much into the results pertaining to height may cast the plant-based milk beverages in a negative light. That would be unfortunate, because almond milk and other drinks do bring needed nutritional content and are far healthier than other options, such as juices and soda.

For the study authors, they say they’ll continue to keep an eye on the growth of the children involved in the study to determine if their height evens out.

“That’s one remaining question. We don’t know if the kids consuming non-cow’s milk, maybe they catch up over time, or maybe they don’t. Time’s going to have to tell,” Maguire told CNN Health. “We do know in general as pediatricians that children who are on a certain percentile line in terms of height tend to stay on that line for the rest of their childhood and into adulthood.”