Should You Drink Milk?

The onetime symbol of purity and goodness has become as controversial as gluten. Here, a guide to the bloat in your dairy aisle and in your stomach.

On a recent trip to Whole Foods, I rounded a display of quinoa macaroni, continued past a fridge stacked with local kimchee and lacto-fermented sauerkraut, ignored the child to my right who’d just shattered a bottle of sparkling matcha tea, and paused for a moment in the mouth of the dairy aisle. There before me were no fewer than 20 types of milk — the typical array of fat contents, of course, but also an entire universe removed from the cow.

“Fifty percent more calcium than milk,” said one carton of almond milk. “A delicious alternative to soy,” noted the label of an “organic oat nondairy beverage.” There was rice milk, hemp milk, coconut milk, cashew milk … enough choices to make the pasta section — which, in the wake of the anti-gluten movement, has forced us to weigh the relative merits of brown-rice pasta versus mung-bean pasta — seem sparse.

Dairy and gluten have become evil twins in “elimination” diets, the holistic therapy of the moment, as people swear they feel less bloated and lethargic without them. (Not incidentally, sales of cow’s milk have essentially flattened in recent years, while nondairy alternatives, led by almond milk, are up nearly 100 percent, reaching about $2 billion in annual sales.) Best-selling authors like the integrative physician Mark Hyman maintain that, like the gluten in wheat, milk elements interact with our gut bacteria in such a way as to trigger an inflammatory response from the immune system.

But this theory, as far as gluten is concerned, has been seriously undermined: Most notable are the findings by a team of Australian researchers who suggest that at least some of the people who think they’re sensitive to gluten (and who don’t have celiac disease, the gluten-induced autoimmune disorder) really aren’t. The true culprit, they argue, may be a group of common carbohydrates lumped under the acronym fodmaps (fermentable oligo-, di-, and monosaccharides and polyols). They’re found in foods like beans, onions, and, yes, milk — lending credibility to those “dairy sensitivity” claims.

Nobody disputes that the sugar in milk, lactose, frequently causes digestive upset. As many as 15 percent of Americans seem to be genuinely lactose intolerant, and we’ll get into the why and what of it on the next page. But for the lactose tolerant, there’s a more basic question: Should you drink milk? Or, more to the point, is it good for you?

Some of those who hold that it is think it’s because they’re winning the raging debate over saturated fat: The old belief that the animal fat in whole milk raises cholesterol levels and promotes heart disease — ushered in during the 1950s by researcher-physiologist Ancel Keys — has newly been called into question. A major BMJ study published this year concluded that diets high in saturated fat are not linked to a higher risk of heart disease. Harvard nutrition researcher Walter Willett, among others, has done a study showing that full-fat milk may confer modest weight-loss benefits compared with low-fat (it would seem that whole milk is more filling, so you subsequently eat less). And according to one recent Harvard School of Public Health study, consumption of dairy fat may actually lower the risk of heart disease. 

But the new pro-fat corner hasn’t conclusively made the case that whole milk is a health food either. Nutrition eminences like Willett are now trying to temper the debate — just because saturated fat isn’t as pernicious as we thought doesn’t make it good. He recommends weighing the healthiness of saturated fat relative to whatever you would be eating in its place: According to a study he co-authored last year, when you replace some of the saturated fats in your diet with unsaturated fats or whole grains, you get an improvement in heart health; with refined starches, you get no gain at all. Such a nuanced, split-the-difference approach doesn’t sit well with those more unapologetically in favor of saturated fat — journalist Nina Teicholz, the author of last year’s briskly selling book The Big Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet, dismisses the Willett logic as “a graceful retreat from a failed [fat] hypothesis.” So as you calculate the merits of whole versus 2 percent, 1 percent, or skim, all you can say for sure is that lower-fat milks don’t have a clear-cut health edge over the higher-fat varieties. They’re just lower in calories (and that may not go very far in helping your waistline, anyway). 

Was milk a simpler nutritional proposition in this country in the days before industrialized farming? Not exactly. Settlers brought the first dairy cows to North America in the early 1600s, and while milk was regarded as a useful source of fuel, milk-borne pathogens like listeria had laid people low before pasteurization became routine in the 1920s. After vitamin D was added to cow’s milk in the ’30s, the beverage became a one-stop-­shopping solution for healthy bone growth and the vitamin-deficiency disease rickets. “Our relationship to dairy was one of reverence,” says Dr. David Katz, the director of Yale’s Prevention Research Center.

And naturally, the dairy industry has wanted to maintain that relationship. (Think of the “Milk. It does a body good” commercials.) But as it turns out — and here’s a recent development where there does seem to be some consensus — regardless of what you learned growing up, you don’t need milk (or any dairy) to enjoy a healthy diet after the age of 2. Authorities like Katz and Willett — and indeed most nutrition scientists, even those whose research is subsidized by the still-powerful National Dairy ­Council — agree that you can get enough calcium and potassium by eating whole grains and leafy green cruciferous vegetables like kale, arugula, and broccoli. (Of course, for families in neighborhoods with inadequate supermarkets, milk might be the easier choice.) Two recent studies published in the BMJ show no connection between calcium consumption and bone breaks in those over 50. Plus, there are the environmental implications: all the methane emissions and water consumption associated with raising enough livestock for people to consume the USDA-recommended three glasses of milk a day. If we actually followed those current “MyPlate” standards, we’d be doubling dairy consumption in the U.S. — what Willett calls a “radical” position.

Ultimately, then, milk is a consumer product, not a medicine. Many of us have no intention of giving up more modest amounts of the stuff that goes so well with coffee, or a bowl of Cheerios, or a superfood smoothie — because we enjoy it. In which case, perhaps the sensible approach to the modern dairy aisle is with your specific needs — and wants — in mind. Each type of milk competing for your attention offers an experience, a health claim, and a projected lifestyle all its own. People going Paleo can turn to additive-free coconut milk. Some might like the silky consistency of soy milk. Others might have taken to vanilla almond milk ever since their local third-wave coffee shop started offering it (perhaps not noticing all the extra sugars and thickening gums in the ingredients). For those of us who don’t shun dairy, there’s whole milk from grass-fed cows, which, according to Michael Pollan, might be the greatest-tasting milk of all.