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The lactose-tolerance mutation (slate.com)
319 points by MaysonL 1607 days ago | hide | past | web | 169 comments | favorite

Access to milk is a great thing, because you get the calories and many nutrients needed to sustain life, and all you need is a cow, goat or sheep (which is mobile) and pasture.

Compare that to cereal crops like wheat or maize or vegetable crops, which require long uninterrupted growing seasons and irrigation.

Why is this important? When a troop of rampaging soldiers cuts through your village and pillages everything in sight, you grab your cows and family and boogey out of there. Essentially, you have a mobile food supply.

In the event of a drought, you have options as well. With wheat or vegetables, no rain == no food. With a dairy animal, you go kill the guy who controls the next pasture and let Old Bessie the cow feast on the grass. (The other key development was the introduction of potatoes, which remain buried under the ground safe from the rampaging army above -- my Irish ancestors subsisted on potatoes hidden from the English taxman and a cow that lived in the house.)

In Europe and the Near East, these things were really important, because there was always pillaging armies marching across the continent. Today, it's unlikely that some Mongol horde is going to loot my supermarket, so I drink milk and eat cheese because they are really tasty.

The importance of Milk/Cows has been recognized in other cultures as well. My ancestors found cows to be so important that they deemed it sacred

Today, India is the largest producer of Milk in the world, and that goes a long way in providing nutrition to its masses.

In India, Cow is more of divine than Bovine. As author rightly mentioned "Agriculture-plus-dairying became the backbone", in Indian civilization, it has been imbibed in culture that they both go hand in hand.Their interdependence is well known Cow eats Grass/waste crops, Cow dung/urine is used as manure for the crop and mosquito repellants etc. And outputs of both are enjoyed by the farmer - Crop and Milk products :)

Why not eat the bulls for meat as well?

Up until recently, most of Indian farming depended on (and still does to a good extent) on Bulls ploughing the fields for seeding. That and bullock carts as transport.

That answers my question then - they get castrated and used for transport.

Bulls make more cows?

You only need one to impregnate lots of cows.

I wonder what happens to the male offspring of Cows in India?

not if you want a reasonably distributed gene pool, diversity of genes is always a good idea

Well, yes. You don't want one bull to do 100% of cows, but one bull can easily do an entire herd, and using In Vitro methods the most valuable bulls fertilise thousands of cows.

What you're alluding to is that milk producing animals are able to turn grass into milk, something we (humans) long ago lost the ability to do. We are unable to digest cellulose for ourselves so we rely on cows and goats and so on to do it for us. Due to the ready availability in per-industrialized Europe of grassland having a cow or goat always means, thanks to the lactose tolerance gene, that humans prosper.

> Various ideas are being kicked around to explain why natural selection promoted milk-drinking, but evolutionary biologists are still puzzled. [...] Those who couldn't drink milk were apt to die before they could reproduce.

The success of the lactose tolerance mutation may be partly due to sexual selection[1]. It's been proposed that neoteny[2] is a key feature of human evolution. The ability to drink milk as an adult is a neotenous trait, and it may have been "accidentally" selected for when other beautiful features were sexually selected.

David Rothenberg's book, Survival of the Beautiful[3], argues that biologists are sometimes "blinded" by natural selection and ignore sexual selection.


[1] - http://en.wikipedia.org/wiki/Sexual_selection

[2] - http://en.wikipedia.org/wiki/Neoteny

[3] - http://blogs.scientificamerican.com/thoughtomics/2012/10/25/...

> The success of the lactose tolerance mutation may be partly due to sexual selection...The ability to drink milk as an adult is a neotenous trait, and it may have been "accidentally" selected for when other beautiful features were sexually selected.

Accidentally? Try getting laid when your GI tract is in rebellion. An accident my ass! (Or some ancestor's lactose-intolerant exploding one.)

When we see a trait that has no obvious fitness benefit, then it makes sense to ask if it might just be a consequence of genes that encode for other, more useful traits. But when a trait such as lactose tolerance has clear benefits for the organism there's no need to complicate the hypothesis without other evidence pointing that way.

I agree, but the mutation has a ridiculously high selection differential, one that probably can't be explained by a single factor.

How, specifically, can sexual selection operate in this case? It would seem necessary that the lactase-production gene, which the article mentions, must have some external effect that's peculiarly attractive. But I don't think it's possible to tell apart lactose-tolerant people by their appearance.

Milk consumption makes males taller and broader [1]. So the sheilas want to breed with the tall milk-fed hottie and not his short, weedy and flatulent lactose-intolerant friend.

[1] http://www.annualreviews.org/doi/abs/10.1146/annurev.nutr.26...

This is incorrect in its context. While milk consumption does aid growth, lactose intolerance in most cases develops during late adolescence and early adulthood. By that time, most of the growth in height has stopped.

Taking your account as fact (I have no data), this does not entirely refute nikatwork. It may be that in past generations lactose intolerance generally developed earlier than it does now. Today's later intolerance developers are the stubborn residue in the gene pool after the tolerance gene became dominant amongst the children of earlier intolerance developers. The assumption that intolerance was not switched off, but slid back to ever later years could be tested in families of multiple living generations whose intolerance is in flux.

You're going to need a citation for "lactose intolerance in most cases develops during late adolescence and early adulthood".

According to this indirect citation [1], lactose intolerance varies by age and race, eg 85% of Chinese are lactose intolerant by age 10.

If a significant percentage of a genetic group develops lactose intolerance by age 10, then yes - it would most definitely affect growth.

[1] http://boards.straightdope.com/sdmb/showthread.php?t=485313

Citation: http://en.wikipedia.org/wiki/Lactose_intolerance#Terminology

Relevant quote - emphasis mine: "Primary lactase deficiency is genetic, only affects adults and is caused by the absence of a lactase persistence allele.[9][10] It is the most common cause of lactose intolerance as a majority of the world's population lacks these alleles.[11]"

edit: Also, I can't believe you linked to some forum called "The Straight Dope" as your citation.

Did you even bother to follow the link? Here, I extracted the reference for you [1].

"Chinese and Japanese populations typically lose between 80 and 90 percent of their ability to digest lactose within three to four years of weaning." (Swagerty et al, 2002)

Ergo, lactose intolerance is a factor in children in some genetic groups. Your citation (sourced from the same wikipedia page) does not refute that.

[1] http://en.wikipedia.org/w/index.php?title=Lactose_intoleranc...

Briefly, one or a few mutations are responsible for both the child-like traits that are selected for sexually as well as other child-like traits such as lactose tolerance. So selecting for the former also results in the latter, because the traits are genetically linked.

Typically neoteny is achieved by mutations that alter developmental timing, and it's easy to imagine that such a mutation could also result in sustained lactase production past the "normal" age.

As for the question of why all lactose-tolerant people aren't visually identifiable, keep in mind that there may not be just one variant of the lactose-tolerance mutation, and perhaps not every variant has complete penetrance. For example, perhaps one gene variant confers a 50% probability of lactose tolerance, but always confers a particular attractive trait.

Sexual selection would operate on a different (neotenous) trait, and the lactase production gene would come along for the ride.

Genes and organsisms are complex beasts, so traits will often be clustered together. An interesting related experiment is one performed on foxes, where they were bred for 'tameness' and gained a whole raft of other dog-like traits: http://www.freerepublic.com/focus/news/807641/posts

But to prove that you need to show that there exists a neotenous trait that improves sexual selection.

Then you need to prove that the lactate gene is in linkage disequilibrium with that gene (thus capable of being "coming along for the ride".

Given the impact of a genetic mutation that improves metabolism, which has its own evolutionary benefits (improved ability to access energy) there seems little reason to invoke this third trait.

We're not really talking about 'proving' things, particularly on an internet forum, but you could start with a relative lack of facial and body hair, larger heads and bigger eyes, as well as more curiosity, less aggression and a more plastic brain. That do?

Just appearing young is an evolutionary advantageous trait if men pursue what they perceive as younger women to breed with (for increased fertility, less chance of stillbirth and defects, etc. - they wouldn't have to know this, the ones that like young looking ones would just have to reproduce more successfully and the trait of looking for it would be bred in without men actually knowing that preferring young women is advantageous in terms of reproduction).

Conversely lactose intolerance could also be unattractive. As a person who is mildly lactose intolerant I can confirm that if I were to drink a tall glass of whole milk I would be a very unattractive person to be around, at worst you'd simply pass out from the assault on your sense of smell.

Side note: a possible attractive quality of lactose tolerance is an increase in calcium intake which can have multiple positive effects on the overal health of the individual including some outward indicators, stronger teeth for example.

I think he's saying that the lactose gene would perhaps be somehow connected with other genes that might have more direct implications to sexual fitness. E.g. the lactose gene would somehow piggy-back other youth-continuing genetic traits.

Milk drinkers smell different than non.

I don't know what it is, but I frickin love milk. It's one of my 4 main liquids (water, milk, coffee, beer) I put down a gallon about every 4 days. In college, I'd drink a half gallon a day. Usually when I eat anything that makes me thristy/is a little salty, like red meat, I"ll crush the milk too. Pasta? it's so carby, I've got to have milk to get some protein to level out the glucose release. Hungover? not only does milk rehydrate me, it gives me much needed calories/energy. Why I'm so dependent, I have no idea. Friends and family know to stock up on extra milk when I visit. It's like water to me. I can't explain why, or how I got to this point.

edit: Growing up, we always had 2% in the house. From college on I drink skim, occasionally (once every few months) I get 1 or 2%, just to up the fat content (I'm a runner, not terribly concerned with weight gain, more or less trying to maintain body mass...)

I'm the same way. I just turned 40, and have been drinking tons of milk my entire life. It's really bad when I travel for business and don't drink much (or any) milk. I go on a binge until my body says "enough." I think I drank 1/2 gallon today alone.

And, just like you, I grew up on 2% until college, when I switched to skim. In the college dining hall, I would fill 3-4 glasses of milk with nearly every meal. My wife has teased me about it for years. :).

Why did you convert to skim? I don't have any viable sources, but I thought skim was not only tasteless, but not any more healthy than other milk. At least one study has shown skim increases cardiovascular plaque.

I don't really like to stand on the stump of "nutritional science," but I always find food choices interesting.

In college I was all about being "ripped" and having a six pack (sexual selection and all that...) So I cut out the fat in my diet pretty well, which is surprisingly easy in an all you can eat food commons. I still ate heavy on the carbs though, as I was working out regularly, and with intensity. Then I got in the habit of drinking it like it's water, at which point it having no taste is almost a good thing for me.

Agreed. Regular milk is only 4% fat, I believe, and skimming it removes most of the fat-soluble vitamins from the milk.

In general, reducing fat (especially the animal kind) is good for modern people, since we tend to get too much of it.

What you said was gospel in 1990, but nowadays there is much dispute over the role of fat in a healthy diet.

Agreed, I thought the optimal ratios of calorie intake is 30% from fat, 30% from protein, and 40% from carbs. fat is 9 calories/gram, and 4 calories/gram for carbs and fat. At least that's what I try to go by when backpacking. but still, at the rate I drink milk, I'd be consuming way too much fat if I upped it to whole...

I believe that the 30/30/40 ratio comes from the zone diet. To my knowledge there hasn't been any scientific verification on why this is the desired ratio. I've seen lots of other people claiming different ratios work better (e.g. some people claiming that 60%+ fat is best). I'm of the opinion that the ratios don't matter nearly as much as food quality. Does anyone have studies/references that can prove me wrong?

Eating non-sick/happy animals and animal products just seems to make more sense to me. Garbage in garbage out.

Reducing fat means it takes more of it to get the feeling of being full. The milk is also full of growth hormones and carbohydrates which we get too much of, so drinking more of it is potentially worse than a bit more fat.

Skim isn't tasteless, though it tastes less. and many people believe high fat diets cause arteriosclerosis.

> Pasta? it's so carby, I've got to have milk to get some protein to level out the glucose release.

How does that work? You get twice as much sugar (lactose) than protein from milk. http://www.wolframalpha.com/input/?i=milk

The wolfram alpha link shows 18g sugar per cup, other sites (and the 2% label in my fridge) show 12g. And 8g protein plus whatever fat.

See also http://nutritiondata.self.com/facts/dairy-and-egg-products/7...

Milk does have a low glycemic index, so it would reduce the average from the pasta: http://www.health.harvard.edu/newsweek/Glycemic_index_and_gl...

Protein slows down the release of that sugar though, giving a more level energy supply [1], important for a runner that likes to carbo-load before races. I'd usually try to get some chicken in the pasta, or in my rice and beans as well (The actual effectiveness of carbo-loading is debatable, yes)

1. http://www.livestrong.com/article/500047-what-factors-slow-t...

The fat from the milk will slow down the metabolism, "leveling out" the release of sugar.

Also lactose takes time to break down...

You don't need milk, you're just used to it.

It only takes a couple of weeks without it for you to no longer crave it. Go long enough, and the taste of milk will actually put you off.

What's the point of this comment? Why should the author give up milk so that the taste puts him off? What benefit would that be to him? And finally, [citation needed]. Milk contains fat and sugar, two things that the human brain is programmed to like. It seems unlikely that not drinking milk for a while would make that stop happening.

Anyway, if the OP likes milk, he should drink it. The "obesity epidemic" is not from people having a glass of milk with their dinner. If you don't like milk, then don't drink it. But getting all high and mighty on some comment site about what tastes other people should experience is just plain irritating.

>What's the point of this comment?

Good question, you seem to be just trying to stir up an emotional argument for no reason. Nobody said he should give it up. Someone simply pointed out that he doesn't need it like he claims he does.

>It seems unlikely that not drinking milk for a while would make that stop happening.

Try it. Taste isn't just a case of "this contains calories so it tastes good". I like the taste of broccoli, and it has very little sugar and fat. Many people have the experience of not consuming milk for a while, then finding they don't like it any more.

You might want to be careful with this. I have heard that if you fully eliminate dairy from your diet for prolonged periods you will actually become lactose intolerant. That said, don't take my word, but I advise doing a little research before giving it up completely. It would suck to confirm that after the fact.

I think that's what happened to me. I can consume milk products except for liquid milk which will make me sick. (I haven't had much trouble when I use it in cooking though.) This is after going on soy for a year, where before that I could drink milk in the truly heroic quantities being discussed elsewhere.

I'm pretty sure if I tried to copy ImprovedSilence's habits now, I would die. I know I would wish for it :-)

I used to be able to say this, then I went on soy for about a year. Didn't have any liquid milk. Now if I have more than a cup I get sick.

I guess I must be missing something, because there's a rather obvious explanation of the article's central paradox: lactose has calories. To wit, it takes about 10kg of milk to make 1kg of hard cheese, i.e. 6000 vs 4000 calories. So if you have milk directly, instead of cheese, you get ~50% more calories. This would presumably make quite a difference for semi-starving pastoral populations in 10,000 BC.

You can preserve cheese for much longer, and use it in much more foods.

Having attempted to make cheese, I can report that it's almost certainly not compatible with hunter-gatherer (ie nomadic) cultures, so the logic seems to support the idea that agriculture came first, then milking, then cheese, and that therefore the change was already happening. That is, whatever caused lactose tolerance to be such a huge evolutionary advantage didn't require cheese to be a large part of the equation.

> agriculture came first, then milking, then cheese

I don't think sequence is quite right. There are several non-agrarian nomadic peoples that raise large land mammals for their milk. Keeping it in the cow/horse/camel keeps it from spoiling.

Cheese and butter just makes it easier to transport the energy without having to transport the cow.

(fermenting it also gives it longevity and was known in much of the ancient world)


Paneer/soft cheese and curd though is very easy to make, and requires just the ability to let the milk settle.

You may not get to creating Emmenthal/Parmesan straight away, but there are many other viable steps prior to modern cheese.

Well, having made beer and wine before, it's not really compatible with previous lifestyles as well. The way we do things in the modern world is not at all similar to the way historic societies worked. In the earliest days, beer was an accident that turned out well. We wouldn't recognize what they called beer. I'm not a historian, but it's possible that what they called cheese was at odds with our modern definition.

First you make something. They you make it good. These days we call it "minimum viable product (MVP)".

It's worth pointing out that our methods and tastes also evolved because the raw materials and industry trends are changing.

Get a bottle of fat milk straight from a cow, leave it on the kitchen table for a couple of days to turn sour (depends on room temperature) and you'll get yogurt, maybe not as thick as the one you can buy at a store, but it's good nonetheless. Then if the batch was good, you can save some of this batch for later batches, for an addition of bacteria cultures, thus with each successive batch you'll get better and better results. There are absolutely no additives needed (unless you make a business out of it, in which case you want predictable results), with the end-result being 100% chemicals free.

Now try doing that with the bottled milk you can find in the stores.

EDIT (reformulated):

So, consumer tastes are changing based on industry trends ... like these fuckers put extra sugar in everything, being a vicious cycle, because extra sugars in foods give dependency on foods with extra sugars in them. And let's not forget of additives like gels for extra-thickness, or dyes, or powder milk, or other chemicals (because degreased milk or yogurt does not resemble real milk or yogurt, so they have to make up for it somehow) and also preservatives for longer shelf life, etc, etc...

Many consumers would turn their nose on real, fat, non-pasteurized milk or on fat barbecued pork neck, because it's somehow unhealthier than McDonalds' burgers or diary products enriched with chemicals.

And tastes are grown, so if people get used to Danone yogurts that never rot, then that's what they start expecting.

Funny story, the punch line for a Danone milk cream in my country on a TV commercial has been "look how well it dissolves". And I was like "oh wow, can cream really do that?". Go figure.

There is absolutely no such thing as "chemical free". Water, lactic acid, casein, and so on, they're all chemicals, even if you have glorified them with a stamp that says "natural".

Your statement is true, but also useless, as in the true spirit of hacker culture, you're arguing semantics.

"Chemicals" when used in the context of food, means "artificial food additives".

You may disagree that such additives are bad for you health - but just how our early ancestors had low-lactose tolerance, we also have low tolerance for such additives. Maybe our children's children will be able to digest such foods better / more efficiently and without side-effects, but in the meantime there's a wealth of research showing strong links between food additives and increasing rates of cancer, obesity and diabetes.

> with the end-result being 100% chemicals free.

I truly doubt that.

It's quite obvious it went this way: agriculture, then domestication (since you need to provide food to domesticate animals), then milking, then cheese-making. There is no question that it was not a nomadic culture thing.

I'm not so sure why this is obvious.

A large part of the domesticated animals bred in e.g. Norway (because I happen to be from there, not for any particular other reason) are bred largely independent of the agriculture.

Goats and sheep have been popular in Norway for a long time exactly because you don't need to provide food for them from a field you tended, but can send them out to graze in untended fields or in particular up in the mountains during the summer, and can if you don't have access to hay from a farm, collect hay/grass from untended fields to serve through winter. While there's certainly benefits to combining the two in climates like Norway where you need to collect a substantial food source for winter, even in Norway that was/is a convenience rather than a pre-requisite.

Up North, the Saami people have been nomadic for as long as we have recorded history of them, without any agricultural tradition, and some communities eventually took up herding and taming reindeer while continuing their nomadic lifestyle, following the migrations of the herds, in large part because while there's copious food for the reindeer, the soil and climate is not conducive to agriculture. They've largely done this without any nearby source of hay or other food from agriculture available at all.

Whether or not there's historical basis for saying agriculture came first or not, I don't know, but there are plenty of examples that shows that agriculture isn't required for domestication.

Raising cattle isn't presupposed on agriculture. It is possible to manage herds of cattle over a wide grazing area without having to tend to feed stock.

Yes, but, when starvation looms, it seems you're better off having the milk directly (if you can).

That's for sure. By the time you have something halfway edible as cheese, a whole village could have died of starvation. Horrible finicky stuff to make, even with modern refrigeration.

Not quite -- fresh cheeses can be made in a matter of hours, and quite dependably. Obviously they don't last as long as the harder kinds, but they're still more stable than milk. Here's one process:


Yeah, but unless you use them like paneer (ie in curries) they taste bland and icky. But I'm a blue cheese or vintage hard cheese man myself.

I always thought the first cheese was made accidentally by storing milk in animal stomachs (which was a natural sort of Rennet). That, and the motion of being carried while riding/moving was enought to create a bsaic cheese/yoghurt.

yhogurt is pretty easy and good for you, too =D

Sorry didn't understand your statement. If it takes 10kg of milk to make 1 kg of cheese. Than eating 1 kg cheese is like drinking 10kgs of milk. How then does milk give you more calories than equivalent quantity(in kgs) of cheese?

You can have 10 kg of coal or 10 kg of greenhouse gases and ash. Guess what gives you more potential calories?

Bacterias split lactose to grow, consuming energy in the process and dissipating it as heat and runaway gases.

Some parts of the milk are discarded when making cheese.

Some being all that delicious whey. Whey chock full of protein! Discarding is optional of course.

You can make several different types of cheeses from whey too (with other stuff). Boiling milk, cream and whey gives you Scandinavian style "brunost" (brown cheese), traditionally mainly made from goats milk, or you can make "prim" (soft spread; not usually considered a cheese) if you add more fluids. Both very sweet.

The conversion process consumes lactase, a sugar that's responsible for a significant part of the calories available in milk. Thus, eating cheese is not calorie equal to the volume of milk needed for it's production.

> Lactase

Lactose :)


This is the fundamental point of the article... Enzyme on/off.

The weight difference is water. But if you loose a third of the calories when converting to cheese then I assume they're in the whey. I doubt that people who were hard up for calories would discard the whey unless they had some cultural objection or superstition.

That may be part of it, but another large part of the difference is that, as previously stated, turning milk into cheese destroys lactose. You get fewer calories from the cheese because microbes already used up some of the calories that were originally in the milk in order to turn it into cheese, and thus those calories are no longer available for you.

> I doubt that people who were hard up for calories would discard the whey unless they had some cultural objection or superstition.

Indeed, Norwegian goat cheese is a whey cheese, made by boiling milk, cream and whey leftover from other production (such as more usual casein based cheese). There are a number of other traditional whey cheeses from other countries as well.

I'm slightly lactose intolerant.

Here's a tip for others - you can buy Lactase pills at a pharmacy and take them just before you eat any meal that contains milk. This gives you the enzymes you need without your body producing in it.

And it's really awesome. I only started doing this a year ago, but now I can eat many more cheeses, drink milkshakes, etc., without feeling bad. And it happens surprisingly often - every time you want to eat pizza, pastas, etc.

Seriously, is you're lactose intolerant, give it a try - it improved my life considerably.

There are also brands of milk that include the enzyme. Even easier.

Well, as another datapoint to study, asians are said to have a near 90% adult lactose intolerance rate. So whatever beneficial natural selection for Europeans that propagated the always-on lactase mutation, the same cultural/agricultural circumstances didn't hold true for asians.

> "asians are said to have a near 90% adult lactose intolerance rate"

I'm very skeptical of this. I was born and raised in Asia, and all of my peers were raised on a diet with regular milk consumption. So either we were a huge cohort of statistical outliers or that number is way, way off.

I do know that lactose intolerance rates for Asians is much higher (and consequently, less socially troublesome due to the fact that dairy is generally not a core part of cuisine), but 90% is way, way, way out there.

+1 to that. Among all the people I've ever known (in India) only 2 people are lactose intolerant. Indian society has, historically, placed a lot of importance on the cow and milk. Indian mythology has rich references to milk and other dairy products for eg. Samudra Manthan [1], Krishna the cowherd [2]. If we were to consider the level of medicine practiced in India (see [3] and [4], for eg.), one would imagine that any real problem of such widespread nature would be heavily studied and discussed about.

[1] http://en.wikipedia.org/wiki/Samudra_manthan

[2] http://en.wikipedia.org/wiki/File:Krishna_with_flute.jpg

[3] http://en.wikipedia.org/wiki/Charaka_Samhita

[4] http://en.wikipedia.org/wiki/Sushruta_Samhita

This is an American usage of the word "asian", which excludes subcontinentals.

Interestingly, my wife and I grew up on milk in India (to adulthood), but found ourselves mildly lactose-intolerant to American milk.

Edit: changed "includes" to "excludes".

And Australian. "Asian" to me has always meant: China/Japan/Malaysia/Indonesia/Korea(s)/Thailand/Vietnam/Phillipines/PNG/Timor/Laos/Cambodia and maybe Burma.

the bacteria in your stomach can handle some of the milk, so anyone can drink a glass

the difference is I can drink a quart of milk (a little under a liter) without any side effects

I've seen these numbers but my experience in Asia (South Korea and Eastern Russia) seems to be the opposite. Milk is not heavily consumed in South Korea, but I've yet to meet more than one or two people who can't drink it.

All of the Indians I know are fine with milk and my understanding is that milk is now part of the regular childhood diet in Japanese school lunches [1].

Anecdotally, I do know a few Chinese Americans who grew up in the U.S., moved to Hong Kong during their middle and highschool years, didn't tough the stuff while there and came back lactose intolerant as adults. So I suppose it may be an acquired skill one has to keep up with? (their younger siblings who didn't make that trans-pacific journey are fine with milk)

1 - http://kyuushoku.blogspot.com/

Certainly not all of Asia. In India, from anecdotal evidence, almost all adults are lactose tolerant.

In the US "Asian" means "East Asian" exclusively, I believe that's what he meant

that itself means that the figure has to be way less than 50%

Wow, really? Do you have a source for this?

Anecdotally, this seems untrue. I was back in China for 2 months earlier this year and milk (fresh, no less, with expiration days of literally 3 days or less) are sold everywhere. Clearly there is a high demand for milk in mainland China (so much so that there are even brands of imported milk from Germany). This was in the capital of Beijing.

I consider Wikipedia a good source for conversational information, and to that effect: http://commons.wikimedia.org/wiki/File:World_map_of_lactose_...

Actually, a little more looking, I think I also found the Yale study it's from. Here's the power point: http://cst.yale.edu/sites/default/files/worldwide distribution of lactose intolerance, madison 2010.pptx

Seeing the extreme gradients at national borders in that map, I am inclined to call shenanigans on that map. It appears to be wildly overgeneralized.

Perhaps the difference is due to the fact that East Asians domesticated different kinds of cereal crops than Europeans did. Perhaps milk wasn't as important in a rice-based diet as it was in a wheat-based diet? (But then again, Indians eat rice and they're lactose tolerant according to the article.)

Or perhaps East Asians developed different kinds of social and economic structures that mitigated the disadvantage of not being able to consume milk.

Or perhaps the necessary mutations just didn't get incorporated into East Asian genes. Also according to the article, the lactose tolerance gene spread as far as India but didn't cross the Himalayas.

Indians started cultivating rice (~ 2000 B.C.) much later than the Chinese (~ 4000 B.C.) [1]. Given the rate at which lactose tolerance spread in Europe, Indians had already developed lactose tolerance by the time they started cultivating rice.

[1]: http://sourcing.indiamart.com/agriculture/articles/origin-an...

Also there is a growing rate (or alert rate) of allergy to milk protein.

Milk allergy: http://en.wikipedia.org/wiki/Milk_allergy

Understanding and Managing Your Child's Food Allergies: http://www.amazon.com/Understanding-Managing-Allergies-Hopki...

In China I heard that many older Chinese people can't drink milk, but the younger generation (who've drank it all their lives) can. Apparently there were lots of parents who couldn't drink milk themselves who would go to the "milk shop" every week to stock up for their kids. (The place I lived had this little store that just sold packets of milkshake and cartons of UHT milk).

I suppose that's why when I visit Hong Kong there's so few milk for sale, and at 4 times the price.

-- asian who drinks milk daily.

Did Asians have access to dairy animals?

> Everywhere that agriculture and civilization went, lactose tolerance came along.

Odd that they don't mention physical displacement: invasion, dispossession, death. The gene would likely have coincided with other developments of civilization, such as weapon technology, greater numbers, greater cooperation, specialised soldiers etc. Maybe there's evidence against it, but odd it's not addressed, with a puzzlingly high "selection differential". Another factor might have been sexual selection, if the new folk were healthier looking etc.

Note they are talking specifically about the West - agriculture and civilization spread throughout the East without this gene.

It's an interesting article, on a topic I've read about before. I think the answer is that is no one answer - maybe milk became fashionable, and the guys who had a regular supply of milk attracted more females, and thus more offspring. Maybe it was fashionable and, if being consumed as yoghurt, somehow acted as medicine to a bacteria getting around at the time. Maybe it was fasionable, had medicinal qualities and gave you stronger bones, so you were more able to survive childbirth and things like battles or hardships.

I'm just glad I'm not lactose intolerant, so thanks to whoever in my billions of ancestors decided to keep at it.

I wonder how much of it is due to having cows and harsh winters.

(as someone with lots of northern European ancestry and lactose intolerance, it's a fun subject. I can still eat cheese and yoghurt and half-digested milk, so it isn't much bother)

Well, the start of dairy wasn't in a cold climate, so I don't know about that. There was clearly some advantage in being able to digest lactose. Maybe it was the occasional winter that had to be lasted through, and having a cow or goat to milk helped out. Anything that weeded out the competition would have done.

I was thinking about it in two stages; among the people that are using dairy, the ones that can easily consume fresh milk have better access to calories during a cold winter (which might be a difficult time to make yoghurt or such).

> Heart disease, diabetes, alcoholism, celiac disease, and perhaps even acne are direct results of the switch to agriculture.

Really? A plant-based whole foods diet is probably the best cure out there for heart disease and type 2 diabetes. (google Dean Ornish, Neil Barnard, John McDougall)

The author tells a good story but his bashing of agriculture is unsupported.

There are big reasons to be skeptical about the claims of Ornish, McDougall, et al., especially given the evidence that low carbohydrate diets have in improving major heart disease and diabetes risk factors.

I don't agree with the OP necessarily that agriculture led to the above diseases (agriculture is a very broad term), but it is true that these are "diseases of civilization" - such disease have conspicuously shown up under Western dietary influence. Cue Gary Taubes and his book, Good Calories / Bad Calories.

I am no expert but another linked story (http://discovermagazine.com/1987/may/02-the-worst-mistake-in...) explains it better why Agriculture had overall deteriorating effect on human health:

1. Early farmers had less access to variety of diet compared to hunter-gatherers. It is hard to disagree with this one. For a lot of Asia, Rice is still the main food and rice on its own contain little more than carbohydrates.

2. Risk of starvation if crops failed.

3. Encouraged crowded societies and deterioration in position of Women. Agriculture forced women to have children often and that in turn impacted their health. I don't know much about Europe but in India Govt. still runs advertisement encouraging Women to have kids at a gap of 3 years or more. I think it is widely held that healthier Mother in general means healthier baby.

There is no way 'Agriculture' has had an "overall deteriorating effect on human health".

I believe the massive population explosion of humans can not be explained without agriculture.

Think about this. Those two statements are not mutually exclusive.

Think about what? Your sentence ends right there.

So billions more people are able to survive somehow now...but our "health" has gone down?

There is the health of the human species...which has gone up undeniably, evidenced by the billions more people being fed...and then there is the health of the individual human.

So you were referring to the health of an individual when discussing agriculture's impact? Sample size seems kinda small. Also...seems that most of us wouldn't be around for that discussion as the non-agricultural food supply would not allow us to be born.

It's because it's delicious and goes really well in lots of foods.

It moderates strong flavors, smooths out acidic drinks, fluffs up eggs among many other thousands of beneficial food uses.

Other dairy products like butter and cheese are key to an immense palette of flavors and cooking techniques.

Dairy is so delicious that I've even seen people with violent milk allergies put up with the consequences just to scarf down a few bites of custard or ice cream.

They can get Lactase pills...

Calories. Cheese has only about 60% the calories of a starting volume of milk. [1]

Plus, animals can graze on land you can't farm, and they're very portable.

[1] http://westhunt.wordpress.com/2012/01/21/the-indo-european-a...

I read once a theory that the enzyme that splits lactose in the body is destroyed by sunlight. People living near the equator have a much higher lactose intolerance because the constant sunshine destroys the enzyme.

Likewise, people in Sweden for example have a 100x higher lactose tolerance, because there's less sunlight throughout the year.

Wow, mampires...

"We became, in the coinage of one paleoanthropologist, “mampires” who feed on the fluids of other animals."

The real irony for me is the instinctual revulsion that many feel about drinking human milk! (As adults, of course, babies sure seem to love it)

It really sucks living in norway with lactose intolerance. Just about every kind of processed food got milk in some form or another in it. Bread, hot dogs, caviar, potati chips. It's mad cow milk disease!

I do value the importance of milk from a survival standpoint, but I think today's milk is a bastardized version of milk our ancestors survived on that they drank directly from the cow. With the whole factory farm system and terrible diets most (American) cows eat, not to mention the steroids and antibiotics that a lot of cows are given, I don't believe the idea that milk is a nutrient packed elixir.

Not hating for those who want to feel good about their love for milk, but I don't think today's milk is much more than a treat and baking ingredient.

Man was drinking milk long before there was a western civilization.

Perhaps people who tolerated milk reared cows. Given that those who were exposed to cowpox survive smallpox, the advantage conferred would have been huge.

The ties between agriculture and herding are not clear. Mongols are nomads and have a diet that is basically just milk.

I believe the benefit of drinking milk is obvious. A herd can take calories from grass and drink mud, while the human enjoys a source of clean, caloric, nutrient rich drink that can go anywhere. Farmers, on the other hand, can just be ran over, pilled or sieged by enemies.

It could be a lot more simple, such as a bacteria that grew on cheese, or a virus that milk protected you from.

This would support massive switch to tolerance (simple survival of the fittest).

It also supports the spread, as a bacteria or virus would not have made it out of the "islands" (himalayas, oceans) and so tolerance wouldn't have been an advantage.

though not in the Americas, Australia, or the Far East.

Does anyone know why some East Asians (such as myself) are lactose tolerant? Is that evidence of interbreeding in the past?

Could be the same mutation, or lack of mutation (depending on the original state of tolerance). However if there is no advantage/disadvantage at a certain point (such as our brains taking over to stop young suckling too long, or ample supply of other foods) then it would remain relatively rare in the gene pool.

Perhaps the opposite was true in Asia and your genes managed to survive where the tolerance was an disadvantage?

I have an obvious bias here (I have a cow milk allergy) but I will be very happy when the use of cow milk becomes nonexistant!

Not trying to be obnoxious, but why?

I'm allergic to cats, and while I might often joke that they're beasts from hell (seriously, have you ever paid attention to cats? They're preternaturally Satanic,) I don't actually wish them any harm.

I know nothing of milk allergies or their severity -- is it so bad that just being near milk will cause you troubles, or is it only ingestion/contact. If the former, I suppose I get it. If the latter, why would it bother you that other people choose to consume it?

As one of the 75% of blacks who is lactose intolerant, I can certainly sympathize with bifrost's post, although I don't want to deprive others of milk products if they enjoy it.

As I was growing up, milk, being recognized as healthy part of a diet, was basically forced on me during school - okay, not literally, but the school lunches only provided milk or chocolate milk, the water fountains didn't work reliability, and the cafeteria staff would always look down on my if I brought my own juice. Sometimes it was easier to just gulp down the milk and then deal with stomach cramps/diarrhea during my afternoon classes followed by rushing home to use the bathroom before I exploded.

One of the best parts about going away to college was being able to select my own beverages with my meal. If you want to have milk, that's fine with me, just don't force me to have to consume it.

Milk Allergy can be dangerous. It depends of the level of sensitiveness. For example a baby can be vaccinated by Glaxo's Infanrix that not say explicitly that contains milk protein and he/she will have rush in the skin, fever, cry all the day and make blood stools. And this is just a small symptom. In the worst case it can have an anaphylactic reaction.

So... it can be really serious.

I hate the taste of milk. Pour yourself a glass of milk and drink some of it. Now go away and come back 5 minutes later. Drink again. It tastes bad now. I quickly changed to Soy Milk and I drank a lot of that instead. However, recently I have stopped all soy products because of the estrogen catalysers in them. I'm now on Almond Milk, I hope I'm good now.

Then why not finish the whole glass?

Why not just skip the milk?

Would pasteurization (or lack thereof pre-1862) have any effect on the research?

I feel a little odd drinking this while I drink a glass of milk >_>

The title sounds like the name of a Big Bang Theory episode

I'm lactose intolerant. I guess I'm a caveman :(

WOW - I cannot believe the false premise this entire article is based on. This is Epigenetics, not mutation or evolution!!! http://en.wikipedia.org/wiki/Epigenetics http://www.pbs.org/wgbh/nova/body/epigenetics.html

The article itself says >Two hundred thousand years later, around 10,000 B.C., this began to change. A genetic mutation appeared, somewhere near modern-day Turkey, that jammed the lactase-production gene permanently in the “on” position.

This is NOT a genetic mutation. The gene was already there but not turned on past the toddler years. I searched this entire page of comments and no one knows or points this out?

Because cereal tastes terrible with water?

Because the dairy industry in the US alone gets $4 billion per year in subsidies from taxpayers?

Considering milk drinking predates both of those considerably, I don't think it is quite that simple.

That said, I find most cereal is much better dry, particularly flavorful cereals like grape nuts. I am not a fan of milk at all.

I love Kashi brand cereals without milk. I buy them, and when I see my roommates eating them with milk, I tell them they're ruining the experience.

Really, I like eating plain Kashi cereals and drinking a glass of milk separately. It provides close to complete nutrition, from protein to fiber to vitamins. I just don't like them combined. Even the plain, tastes-like-cardboard Kashi cereals, I eat like a snack.

You must have a lot better teeth than I do... I eat Grape Nuts about four times a week and can't imagine eating even a bite without milk on them to make them a bit softer.

There is a trick to it, you have to kind of grind them with themselves. Grapenuts is actually the only cereal that I can stand with milk as well, but I prefer them usually without.

I've found almond milk to be an excellent replacement for cereal. Better than soy anyways.

You should try vanilla Silk, if you live somewhere it's available. Silk is the brand of soy milk that made me realize soy milk is better than cow milk.

And the sugar content? that might explain it. =/ Almond is drinkable with 40% of the calories.

There's unsweetened (and unflavored) soy milk. Don't know about unsweetened vanilla soy.

For the unsweetened unflavored variety, my local Whole Foods carries Silk, 365, and/or Earth Balance. All three have about 1-2 g sugar per cup, instead of 6-8g in normal (sweetened) soy milk. Some other kinds of milk are worse. I used to know someone who drank goat's milk and some other powdered milk that had 11g and 12g sugar per cup, respectively.

My cereal is moderately low on sugar already (6g per serving among 30g carbs), and it took some getting used to it with low-sugar soy milk, but I can't go back now. If I have to use "normal" (really: sweetened) soy milk, which is still only 6 or 7g sugar per cup, I can feel the sugar rush and it makes me mad.

It's made me hypersensitive to (added) sugar in most foods. I recently tried drinking some sweetened almond milk and I couldn't drink it. It was awful.

For my money, Almond's unsweetened flavour profile wins hands down. It has 1/2 the calories of "unsweetened" Silk. Here are some data for those interested in the comparison. The issue is that most people don't understand what they are drinking.

Almond milk has 60 cal per 12 oz,

Vanilla Silk has 150, "Unsweetened" silk has 120.

Coca Cola has ~145






It's weird how almond, soy or coconut liquids can legally be called "milk" none of those sources have nipples. Coffee is liquid from fermented beans similar to soy it's no more milk than soy is.

I know here in Canada for decades margarine had to be smuggled into the country, when it was legal it couldn't be yellow like butter (but even butter has artificial yellow colour added), it certainly couldn't be called butter.

They can be called "milk" legally because the definition of milk includes the whitish fluid produced by plants. The dairy industry has tried to argue against its use "to prevent consumer confusion" to no avail: http://www.motherjones.com/blue-marble/2010/04/dairy-lobby-t...

Lewis Black said it (ranted it?) better: "There's no such thing as soy milk, okay? And I know that because there's no soy tit, now is there? I don't know a lot, but I know you need a breast for milk."—Rules of Enragement, "Ireland and Health", 7:04-7:11.

> I know here in Canada for decades margarine had to be smuggled into the country

Sounds like anticompetitive political corruption by the dairy industry; I can't imagine how that protects consumers.

Do you also have a problem with ground peanut spread being called "peanut butter"?

I don't think it was anticompetitive reasons although the end result was that I believe it was farmers created a market for butter that margarine would benefit from.

As for PB I'm not a dairy farmer.

IIRC, some U.S. states (Wisconsin might have been one) had similar laws. The margarine companies used the workaround of including a separate food coloring packet, which the customer could mix in at home.

But then what is the point? I know why manufacturers want to defraud consumers, but do consumers really want to defraud their families?

It's not about defrauding anyone in this case: Margarine looks disgusting without added colour. Even if you prefer margarine or have made a fully informed choice you might still very well prefer to add colour to it before using it.

The reason for laws restricting colour additions to margarine was explicitly because it is sufficiently close to butter in taste, texture and usage that it created a substantial competitive pressure on butter sales because people would happily pick margarine over butter to save money. So much so that the separate coloring failed to stem the growing demand.

Calling margarine "butter" is not the same as calling coconut liquid "milk" - it's called "coconut milk".

I guess it's all about the color, see milk glass.

On the other hand, we do have peanut butter, cocoa butter, apple butter...

Coconut milk is more closer to cow's milk with regards to fat content, however almond milk is indeed excellent.

I don't think Coconut milk is intended as a replacement for regular/soy milk though. Its even packaged in tin cans, so I'm assuming the primary usage is as an ingredient in Southeast Asian foods (esp. Thai Curries)

I think the commenter you're replying to is referring to a type of drink that's a milk-substitute containing coconuts, not the canned stuff that's got tons of coconut oil (and thus very fatty) ... though I love both, it's kind of confusing that their names are very similar.

[1] http://dairyfreecooking.about.com/od/dairyfreebasics/tp/Milk...

Did you read beyond the title? Subsidies wouldn't matter if everyone was lactose-intolerant. The article is an interesting discussion of how we don't really understand why adult humans are able to drink milk at all.

Also, the title here has nothing to do with the story on Slate.

It's in the URL, I wonder if Slate updated it because it was confusing. I also initially read it as "keep drinking (even in 2012)" when it's really "keep drinking into adulthood."

I might be remembering incorrectly but I believe that my grandma told me once that they used to use water on their cereal instead of milk. I have not been able to find any sources of it being true (everywhere) so it might have been just their family or perhaps because of the depression or other circumstances.

I can believe it. More than a decade after the Depression, my grandma saved money by feeding my dad and his brothers watered-down reconstituted powdered milk. There was an entire category of foods my grandpa didn't allow in their house because he ate them as a child in the Depression, including turnips, rutabagas, millet, and certain kinds of beans, but they still felt like they couldn't afford to use the full ratio of milk powder.

Was this meant to be funny?

If not you clearly didn't read the article, as this is basically an article about human evolution/genetic mutation.

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