Cow's milk is good food, but only for baby calves.
Baby calves grow fast. They gain about a pound and a half per day, and by their first birthday they’ve increased their weight by eight times or more. Human infants grow quickly, too, tripling their weight by 12 months. But by the toddler years, children are putting on only about 4 or 5 pounds per year. So how could cow’s milk be a good choice for slow-growing toddlers and fast-growing calves? A new study from Indiana University suggests that it isn’t.
Dr. Andrea Wiley compared cow’s milk intake and growth in children aged 2 to 10 years and found that milk-drinking was associated with higher body mass index (BMI). Her results were published online this month in the American Journal of Biology.
The data came from the National Health and Nutrition Examination Survey (NHANES), an annual survey of health, diet and nutritional status of Americans. Among the nearly 4,000 children studied, milk drinking was associated with higher BMI even after controlling for calorie intake. This suggests that something else in milk—maybe related to protein or mineral content—might impact weight gain. And in the school-aged children, milk was associated only with greater weight, not with height. Among the younger children, it was associated with both.
The findings suggest that a childhood dietary pattern including milk could “upregulate growth” in children, extending the rapid growth rate of infancy beyond the first birthday. Nutritionists have long known that “growing like a weed” is not necessarily a good thing. For example, breastfeeding is widely recognized as the ideal choice for infants, but breastfed infants grow more slowly than those fed cow’s milk formula. And some research has linked high BMI in childhood to later risk for obesity and chronic disease. High consumption of milk has also been associated with low iron levels in toddlers. That’s because milk doesn’t contain iron and it interferes with iron absorption from other foods.
It's no surprise that cow’s milk may not be an ideal food for humans. In the evolutionary scheme of things, dairy consumption is a recent phenomenon. Prior to the introduction of agriculture—some 10,000 years ago—children didn’t drink any milk once they were weaned. Even if humans had been able to obtain milk from wild animals, they wouldn’t have been able to digest it because of its lactose content. Today, the number of adults throughout the world who can’t digest lactose (the sugar in milk) continues to be much greater than the number who can.
Evolution has long suggested that cow’s milk isn’t a food for humans. It's designed for the super-fast growth and development of a different species at a specific stage of life. Cow’s milk is for baby cows; human milk is for baby humans. And once they are weaned, nobody needs any milk at all.
For more information on why milk-free diets are the best choice and for ideas on meeting calcium needs, check these articles:
Alternatives to Dairy
More Reasons to Go Dairy-free
Teens Don't Need Milk
Meeting Calcium Needs on a Dairy-free Diet
Plant Foods are Good for Bone Health
| Check out my blog The Vegan Dietitian to learn more about vegan diet and lifestyle! |
Comments
We humans are mammals. For mammals it is normal (and necessary) to stop drinking milk when we start eating solid foods.
Interesting article. Milk contains many biologically active molecules including enzymes, hormones and growth factors including seven pituitary hormones, seven steroid hormones, seven hypothalamic hormones, eight gastrointestinal peptides, six thyroid and parathyroid hormones, 11 growth factors and nine other biologically active compounds. The concern here is that these signalling molecules that have evolved to direct the rapid growth of a calf into a cow may initiate inappropriate signalling pathways in the human body that may lead to illnesses and diseases such as cancer. See the Vegetarian & Vegan Foundation's White Lies report for more information.
Got something to say?
Examiner.com is looking for writers, photographers, and videographers to join the fastest growing group of local insiders. If you are interested in growing your online rep apply to be an Examiner today!