Why China developed a fresh taste for milk

China’s appetite for milk has exploded in recent years. The nation of nearly 1.4 billion people is now the world’s second largest consumer of dairy products, and imports are flying over the border, with dairies from New Zealand to Germany topping off the behemoth’s demands for milk.

An intriguing little detail in all this frothy commerce is that many people in China, like much of Asia, are lactose intolerant. Human children produce an enzyme that allows them to digest milk, but in much of the world, its levels taper off as they grow up.

People of European descent are somewhat unusual in that they mostly continue to digest dairy effortlessly as adults. In China, a much-cited study estimated that 92% of adults had trouble absorbing lactose; more recently, China’s preventative medicine agency suggested that by the time kids are 11 to 13 years old, around 40% have lost the ability to digest it.

So how exactly is all this milk swilling working, and how did China come to have such gusto for dairy?

For most of the 20th Century, milk had a relatively low profile in China, says Thomas Dubois, a professor of humanities at Beijing Normal University, who has studied the nation’s dairy industry. There were many tiny dairy farms in the northeast, with an average of four cows a farm, and their milk made its way by train to the Russian-influenced city of Harbin, where most of it was made into butter and cheese. Bigger dairies eventually appeared in coastal cities, however. With several dips caused by invasions, famines, and other downturns, large-scale production gathered speed.

By the 1980s in China, powdered milk was a health product, and it was generally used for babies and for older folks. In the early 80s there was a run on milk in Beijing, Dubois relates, and people were waiting in line all night for it. “You had a really strict ration on how much you were able to get for your household,” says Dubois. “This was really, really prized.

“Maybe even more than children, milk was considered food for elderly. I just know so many people who all have the same story from this very early time, of sneaking into their family’s milk supply, and trying something – we know it’s for the baby or grandma, but trying a little and thinking, ‘This is the most delicious thing I’ve ever had in my life’,” he says.

Then, too, there was the phenomenon of White Rabbit candy. This Chinese confection is made of milk solids, like a chewy white caramel, and it’s said that one glass of milk equals seven pieces of candy. When Richard Nixon visited China, he was given White Rabbit as a gift.

“If you’re going to give this to Nixon in the early 70s,” Dubois notes, “this is about as good as you can get.”

By the 1990s and early 2000s, it was much easier to get liquid milk in China. Enormous dairy operations were built, some of the largest in the world. Even a deliberate adulteration scandal in 2008 – melamine was added to baby formula to boost its apparent protein content, killing at least six children and making thousands ill – did not dent the consumption of milk over the long term. In an article on Chinese dairy, Dubois writes that sales for the two largest Chinese providers fell 80% in the first 10 days after the scandal was revealed, but soon rebounded. 

Milk and other dairy products, especially long-lasting UHT milk and drinkable yoghurts, are now readily and cheaply available in Chinese cities. Pizza Hut, while still a more formal dining experience in China than in the US, can be spotted crowded with school kids, eating gobs of melted cheese that older generations would likely avoid. (Read more: Why do humans drink animal milk?)

So how does the lactose intolerance scientists have recorded come into all this? It’s something Dubois has wondered about for years. “When I first started the project, I would walk up to strangers drinking milk and ask how they deal with digestive problems,” he says. “The answer was consistent: “If it bothers me, I stop.”  

Additionally, people didn’t seem to seek out lactose-free milk, although such products can be found if you look.

One reason may be that a great deal of the dairy consumed in China is eaten as yoghurt. The fermentation process breaks lactose down, so there’s not much left to bother people. As well, the volume of lactose consumed has a big effect on the subsequent gastrointestinal effects. If people don’t consume more than what’s in a cup of milk a day, they generally don’t run into trouble. A little bit of dairy every day is not likely to set people off.

So, if all this dairy-eating isn’t causing people problems, will it have an effect on young people’s digestions in the long term? Will their enzymes start sticking around longer?

“I guess the real wildcard is whether younger people have retained the ability to digest lactose by virtue of consuming dairy since childhood,” says Dubois. “That’s something I can’t comment on, but the inability of lactose-free or low products to command the consumer mainstream suggests that the problem is not as big as I had once thought it was.”