If Asians Are Lactose Intolerant, Why All the Milk Tea? (with Dr. Jennifer Dubois)

[00:00] So why doesn’t China traditionally have cheese? It’s a common question, and if you’ve ever spent   some time online, you’ve probably seen  an answer with a graphic a bit like this.  Lactose intolerance around the world. For China,  we’re at 92%. So, of course you’re not going to  

[00:19] develop a dairy industry if no one can eat it –  and of course it’s why China’s always been the   land of tofu… so no milk, no yoghurt, no cheese….  simple question, simple answer, case closed.  

[00:34] I live in China, and there’s nothing more Chinese  than our collective obsession over milk tea.   It started in Hong Kong with Hong Kong style  milk tea, then that was layered with boba  

[00:49] milk tea from Taiwan, and now throughout the  country you can find a ton of milk tea shops.   Milk tea streets like this are a  popular hangout for young people,   there’s premium brands like HeyTea  with their famous cheese froth,  

[01:05] and in every single little town around the country  you’d at least be able to find one Mixue.   But that’s just China, what about  Japan, 98% lactose intolerant,  

[01:17] and they seem to love their royal milk tea. What  about southeast Asia, 96% lactose intolerant,   but in Bangkok you can’t go far without a Thai  style street milk tea, or what about Vietnam,  

[01:31] isn’t their coffee like half condensed milk? ranging from 20%-68%? But isn’t Italy the  place that actually invented cappuccino?  

[01:46] So I’m not going to lie, this whole  thing is starting to make me feel   like a lactose intolerance truther. consensus that there is a specific gene  for breaking down lactose – the LCT gene,  

[02:01] and apparently 92% of China don’t have it. But  there has to be something else going on here.   So, I’m Cantonese, I grew up with milk,  yogurt, and ice cream. And I lived in Shunde,  

[02:15] where they’re famous for their deep fried milk,  stir fried milk, and double skinned milk.   And nowadays in China, every kid’s favorite is  pizza. Which sometimes you might be able to find  

[02:28] it without tomato sauce, but never without cheese. So with these questions in mind, we reached out   to a proper expert: Dr Jennifer Dubois, who  is a professor of Biochemistry at Montana  

[02:43] State University and runs the Dubois  lab, and specializes in microbiome. So, uh, Jen is our professor here. Sounds good.  Um, so let's talk about lactose intolerant  

[03:01] because I also did a gene test and it says that  I'm also genetically lactose intolerant. Um,   so but I drink milk all the time. So what  does that mean to be lactose intolerant?

[03:15] So lactose intolerance is actually a  really interesting genetic condition.   So I have a model of lactose. It's two simple  sugars linked together. And there's a single  

[03:28] enzyme called lactase that pops them apart.  And if you lack the enzyme that's capable of   doing that, you can't digest lactose any  further. But the genetic reason behind a  

[03:43] lactose deficiency is that you just  simply aren't making the functional   lactase gene - product. And that's because  lactose, which is the major sugar in milk,  

[03:56] is baby food. So if you're an adult, you  don't have any real need for lactose. I see People always say that if you're lactose  intolerant, it will cause some kind of   discomfort. I got full very fast from drinking  milk straight or sometimes even eating cheese.  

[04:16] If I eat a lot of cheese, I'll also get full.  Um… is there any like kind of common diagnosis? So, lactose intolerance is sort of a spectrum.  People can experience a little bit of discomfort  

[04:32] or they can experience a lot of it. But if you  experience really significant lactose intolerance,   enough to take you to a doctor, they'll ask you  to breathe into a tube. And if you're exhaling  

[04:48] hydrogen, hydrogen gas like the Hindenburg, that's  the easiest diagnostic for lactose intolerance.   And the reason why somebody who's lactose  intolerant would exhale hydrogen is that they're  

[05:04] not digesting their lactose. Their microbiome  is digesting their lactose, by fermentation. Oh! So if you are one of those 30% of the  people on the planet who can actually make  

[05:18] functional lactase well into adulthood,  you would not be exhaling hydrogen gas.   But if you're relying on your microbiome  to do it for you, then you would probably  

[05:30] be exhaling a lot of it and that's part  of the reason for your discomfort. Now,   if you are a regular drinker of milk and there  are people who drink milk every day despite  

[05:44] being lactose intolerant, then you probably  have a very well-trained microbiome. And your   microbiome is probably chalk full of microbes that  are fermenting your lactose to make hydrogen gas.

[05:59] And these are called lactobacilli.  And if you, like me, are a lactose   intolerant person who likes yogurt and  you look at the cultures in your yogurt,  

[06:12] you'll see that they say “L. acidophilus,  L. casei, L. rhamnosus”. And the L is for   the genus name Lactobacilli. So these are  lactose consuming microbes that live in  

[06:28] your GI tract and they're enjoying all that  lactose that is causing you a problem. Making   hydrogen gas. So that means our guts making  yogurt for us. Your gut is making it for you.

[06:43] And that can cause a little bit of discomfort.  But there are people in Africa for example   these Somali herdsmen who are completely lactose  intolerant genetically but who consume at least  

[06:58] a half liter of milk every day as part of their  diet because that's how they survive. Although   we do know that things like lactobacilli are  almost universal. Almost every person on Earth  

[07:12] is going to have some kind of lactose digesting  organism in them. Whether you have a huge army of   them or just a small little friendly band  might have more to do with what you eat.

[07:29] Now if you're the sort of person who really  rarely drinks milk and one fine day you decide   that you're going to go out for an ice cream party  or you're going to drink a liter's worth of milk,  

[07:43] then you might experience some very bad  clinical symptoms because it turns out   it takes a while to build up a microbiome that  has enough lactobacilli to do this work for you.  

[07:56] So, what you're probably going to feel is sort of  like you just ate a sweater! Because you've filled   your GI tract with something that you can't  digest. Your microbiome can't digest. And so,  

[08:09] what happens is a bunch of water will rush  into your GI tract. It'll really inflate your   intestines and you might end up with a little bit  of diarrhea. So that's when people end up with a  

[08:25] clinical manifestation that might actually send  them to the doctor. But if if the consequence is,   you know, feeling full because you have a  little bit of extra gas or maybe you have  

[08:38] extra water retained in your GI tract, that's not  the worst thing in the world? It would probably be   clinical if you were vomiting or really showing  something that took you to a doctor and then  

[08:53] they would probably say you should take lactase  pills. If you really have to have that milk tea.  So right now my understanding is that the  effect has a couple different factors.  

[09:09] One very important is that they have a  microbiome that can that can help them digest.  If you're lacking the ability to produce lactase,  then yes, having a well functioning microbiome  

[09:24] that can do the work for you is very important.  And part of that well functioning microbiome in   terms of your comfort could be when you ferment  the lactose… a downstream product of that is  

[09:37] hydrogen gas. And hydrogen gas is a gas, and it's  going to literally bloat you up. And so if you   have a friend of that initial consumer who likes  to eat the hydrogen, they can cooperate. And so,  

[09:53] you know, this is how I imagine these people  who are the Somali herdsmen who are really   punching above their weight drinking a liter  of milk a day. They probably have a very well-  

[10:07] conditioned microbiome, not only to break down  the lactose but to take care of all the downstream   metabolic products that come after. And they  feel plenty fine. So, so I really appreciate  

[10:23] your time and help today to help me a lactose  intolerant Asian understand what is going on   with my gut and why I can actually eat and consume  dairy. And most importantly, I learned this pill  

[10:37] lactase. I'm going to bring it with me next  time traveling to a dairy heavy area so that   I can eat all the things that I love. Do that!  Especially when you're in Europe and all those  

[10:50] happy cheese eaters are- Yeah, I know! -making fun  of you because you can't enjoy with them. I know.   It's such a shame that I feel full so fast now  that I know the trick. They say it helps! Yeah,  

[11:05] that that will definitely be my biggest  takeaway for today as a food lover. So again,   thank you very much for your time. You're very  welcome, Steph, and it was great meeting you.

[11:18] So besides bringing lactase pills to  any potential cheese feasts in France,   my biggest takeaway is that this map is  probably better communicated in the inverse.  

[11:30] We see a specific genetic mutation  that allows some people to digest   and get calories from lactose into adulthood. But the phenotype of lactose intolerance  is messy, it’s a spectrum, and some people  

[11:43] like those Somali herdsmen, they have a  microbiome that makes no problem at all.   Which brings us back to the original  question: why didn’t China have cheese? 

[11:55] For this, our friend and food historian Thomas  Dubois – yes, the same Dubois – has his answer.  That lactose intolerance was part of it, but it’s  also a chicken and the egg kind of phenomenon.  

[12:09] Sure, souring and coagulation can solve  most of the digestibility issues (like   71% intolerant Turkey), but you also have  a lot less of incentives to make those  

[12:24] higher-value-add products when you don’t  have a base dairy industry to begin with. But China’s a big place, and you do still see  it in pockets… like our old home of Shunde,   or our current home of Yunnan.

[12:40] like to humbly submit my own hypothesis  of ‘why’ – it’s ‘no why’. Just because.  It’s definitely not a satisfying answer,  but sometimes it’s just the way it is.

[12:54] Because, why doesn’t India have tofu? Or  why doesn’t Scandinavia have fish sauce,   or why doesn’t Italy have shrimp paste?  Sometimes it’s just the way culture evolves.

[13:08] When we look at history, we can usually  do a pretty good job figuring out why   something happened, but it’s a lot harder  to answer why something didn’t happen. Sometimes, it’s not even knowable. Sometimes,  that’s just the way the cookie crumbles.  

[13:24] So right! I know this was a bit of a weird one,  we just really want to get to the bottom of this.   So huge thank you to Jenn and all of the  Dubois out there for helping us to answer   these questions, recipe video will be back next  week… in the meantime, thank you for everyone  

[13:41] that’s supporting us on Patreon, and of course,  subscribe for more Chinese milk loving videos.