Do we really need milk?
Posted May 4, 2016
Once considered "nature's perfect food," milk is falling out of favor with consumers — unless it's made from almonds or cashews.
Sales of dairy milk plunged 7 percent in 2015 and are expected to decline more over the next five years as plant-based beverages consume an increasing share of the market. This stands to reignite a smoldering debate: Do we need milk to be healthy or not?
On one side are vegans, environmental activists and the occasional doctor who say milk consumption after infancy is unnatural and makes people sick, and that large-scale dairy farming hurts the planet. But families that shun cow milk do so over the objection of many pediatricians, who, like the U.S. government, insist that dairy products are an essential component of a healthful diet.
“The reason dairy products are a separate category on My Plate (the government's dietary recommendations) is that there’s really nothing close as far as calcium and phosphorus and Vitamin D,” said Dr. Mark Corkins, chief of pediatric gastroenterology and nutrition at the University of Tennessee Medical Center. "Yes, there's calcium in spinach, but are you going to eat 10 servings of spinach every day to get your calcium?"
About 40 years ago, Americans drank a cup and a half of milk every day; now they drink less than a cup, according to the U.S. Department of Agriculture. Unless we're getting that calcium elsewhere, the decline in milk consumption may become become evident in the nation's health, some doctors say.
Eat your calcium?
Calcium is one of the most important minerals; it's stored mostly in our teeth and bones, and deficiencies can cause bones to weaken and break. Calcium deficiency is a cause of osteoporosis and low bone density, which affects more than half of Americans over the age of 50. It's also been blamed for an increase in the number of broken bones children suffer.
But milk is not the only place to get it. Other quality sources of calcium include collards, salmon, oranges and almonds. (A cup of boiled collards, while not appetizing to most children, contains more calcium than a cup of skim milk.)
"Calcium is essential. Milk is high in calcium. It does not follow that milk is essential," writes Alissa Hamilton in her 2015 book "Got Milked?"
Hamilton, a Toronto scholar with degrees in law and environmental studies, blasted the orange-juice industry in 2009's "Squeezed: What You Don't Know About Orange Juice." She's now after dairy, arguing that milk's "privileged place" in the American diet is undeserved.
Hamilton said she’s not anti-dairy; she drinks kefir, a fermented beverage similar to yogurt. But she believes Canada and the U.S. should stop emphasizing dairy in their dietary guidelines. “Health Canada and the USDA say dairy is essential to a healthy diet. But there are plenty of people who don’t eat dairy who are healthy and function very well without it.”
She said that the World Health Organization recommends half as much calcium as the USDA guidelines do, and that many ethnic groups can’t tolerate dairy. Studies have shown that up to 90 percent of Asians and 70 percent of African-Americans have some degree of lactose intolerance.
Corkins agrees that some people shouldn't consume dairy: in particular, the estimated 1 percent or less of Americans who are allergic to milk, and the 25 percent of the general population that is lactose intolerant or sensitive. The celebrated food writer Mark Bittman is among them: In a New York Times column in 2012, he detailed how giving up dairy improved his health and argued that "nature's perfect food" is water, not milk.
But for the majority of Americans, Corkins said, three servings of dairy of day are a good way to the calcium our bodies need, just like the American Academy of Pediatricians and the U.S. dietary guidelines say. He dismisses arguments that milk drinking after infancy is unnatural.
"They say we're the only species that drinks milk (after weaning). Well, we do a lot of things other species don't do. We also wear clothes and drive cars," he said.
Milk drinking among humans, however, was rare until relatively recently, said E. Melanie DuPuis, professor and chairwoman of the environmental studies and science department at Pace University in New York, and author of "Nature's Perfect Food" and "Dangerous Digestion."
Until the middle of the 19th century, if adults drank milk, it was usually fermented buttermilk, similar to kefir. "People were really into butter, but they weren't much about milk," DuPuis said.
That began to change in the Second Great Awakening, between 1790 and 1840, when religious leaders began to tout milk as a healthful beverage that could replace its less wholesome alternatives: alcoholic cider, beer and spirits. (Founding Father Benjamin Rush put milk near the top of his famed "temperance thermometer," which ranked beverages in order of their moral efficacy. Only water was better.)
When calcium matters most
Even with the recent decline in sales, 91 percent of Americans consume dairy milk, according to new research by Mintel. Only 57 percent drink it as a beverage, however; the other 34 percent add it to cereal or use it as a cooking ingredient.
Although milk consumption tends to decline as people get older, and calcium is important at any age, calcium is especially important in young adulthood since our bodies continue to build bone mass up to age 30. By age 40, it begins to decline.
Pediatricians rue the decline of milk drinking in adolescence, when teens tend to choose soda or sports drinks over milk — although the recent craze of chocolate milk as a post-workout treat may change that.
“Every time you drink it doesn’t need to be dairy, but you need an adequate intake. People think a little bit of cheese on a piece of pizza is going to be a dairy serving,” Corkins said.
In fact, even as milk declines, cheese and yogurt consumption is up, notes Dr. Walter Willett, professor and chairman of the Department of Nutrition at Harvard T.H. Chan School of Public Health in Boston.
Willett has been a high-profile advocate of consuming less dairy; he believes the USDA recommendations are overblown, and he led research that showed increased milk drinking does not prevent fractures.
“We don’t really need the large amounts of dairy foods that have been recommended; indeed dairy foods are not essential, and a high dairy food supply will be inherently unhealthy as it will include a large amount of unhealthy fat,” he said.
“A modest amount of dairy consumption, such as one serving per day, is fine, and it does seem that consuming much of this as yogurt may have some health advantage,” he said.
At Pace University, DuPuis, too, advocates moderation.
"I tend to advocate not eating as much meat as the Beef Council would want you to have, and not drinking as much milk as the Dairy Council wants you to,” she said.