Sorry for taking so long to finish up on diabetes—the diabetes project has turned out to be more complicated than I thought and is now in its 3rd revision. I’m trying to do something useful that does not read like a PhD thesis.
I have also been on service lately, which is fatiguing.
So, to relax, I decided to get into a semi-religious argument about raw milk.
Recently, here, there has been an outbreak of toxigenic E. coli infection in people who have obtained raw milk from an area farm. Obtaining and drinking raw milk is semi-legal in this state.
E. coli (an organism) is a normal resident in cow bowels and in cow manure. It doesn’t bother the cows but is a major player in lethal food poisoning outbreaks in people (think Jack-in-the-Box). It is fairly obvious how this bug got into the milk—perhaps that was what gave it some special flavor. As far as I know, five people were infected: two children were hospitalized, no deaths. The total number of people actually infected is, of course, unknown, as this farm’s sales practices did violate the state law here, and the enthusiasts may be reluctant to report unless they were very ill.
In the cow, geographically, the place where the manure comes out is fairly close to where the milk comes out. If the manure is on the floor, it is even closer. It is not hard to see how in the absence of very careful practice, the two could become mingled. This bug reproduces about every 20 minutes in a good growth medium, so it doesn’t take a lot of them to get a big population very quickly.
Did you see the movie Fiddler on the Roof? Tevya was the milkman. He milked his cow in the small stall (when was it last cleaned?), into a bucket (same question), then into a larger container (and again). He had no refrigeration. Then he went through the village ladling it out with a utensil that was banging around in his cart. On a larger scale, this was about what milk production was like in this country at the turn of the twentieth century, and, as a result, milk was the second most important source of food borne disease. Only contaminated water was worse, at that time.
The recognized diseases then associated with milk were primarily typhoid and tuberculosis. Disease related to E. coli, listeria monocytogenes (more about this later), and other salmonella were described, but their relationship to milk was not clear then. These were very serious and common diseases at the time.
The problem was overcome by pasteurization. The term pasteurization refers to a technique initially ascribed to Louis Pasteur. He was a chemist by training in mid 1800’s France, when France was the center of true scientific thought and practice. The story is that he was studying the formation of tartaric acid crystals in wine, looking at it with a microscope, when he observed microscopic entities that he associated with different types of spoilage in the wines. He decided these were alive, and began a career as a microbiologist. One of his early interests was how to keep the wine from going bad, and he found that heating the wine eliminated what he was seeing and preserved the wine. He later applied this to beer, with mixed results. He never applied this technique to milk. (Who in France drank milk as an adult?)
The technique has since been applied to many different foodstuffs, including milk. Depending on how it is done, it can eliminate virtually all of the organisms in a material. It was applied to milk in the early twentieth century bringing a miraculous drop in milk-borne disease. When this was combined with testing dairy herds for TB, and eliminating it, milk-borne disease was practically eliminated. When was the last time you heard of milk-borne outbreak from supermarket (highly regulated) milk?
Like many other previous biologic terrors (such as polio), milk-borne disease is not known to current generations, and therefore has no ability to induce fear. Outbreaks of these diseases in small populations don’t get much attention. Nonetheless, they are still out there.
The primary pathogens out there now in raw milk are toxigenic E. coli, salmonella, and listeria monocytogenes. The last is a bug not well known in the population, but well known to us in critical care and neurology as it tends to cause meningitis and sepsis (very bad), particularly in people who have lost their spleen. There are others. There was an outbreak in Minnesota several years back of a diarrheal disease, Brainerd diarrhea, linked to raw milk from a specific farm. No clear etiology was found. The infected had the disease for many months. There have been outbreaks of listeria particularly in the southwest, traced to unpasteurized cheese brought up from Mexico.
Raw milk has become a cause célèbre, very trendy, in this country. It is mostly illegal by state laws, so obtaining it has the extra cachet of defying The Man. It is available through clubs, on farms, and in a semi-underground economy; usually expensive. Its proponents are very enthusiastic, stating that there are almost magical properties of cow’s milk that will improve the person – which magical properties are destroyed by pasteurization. I see many references to how raw milk is supposed to improve the immune system, although I’m not sure how that is defined, what evidence there is, or even what evidence there could be (how would you study this in a healthy population?).
And considering that the immune system of the healthy human being is pretty robust (after all, there are about 6 billion of us), do we need our immune system tweaked? I have taken care of enough people with lupus, rheumatoid arthritis, various forms of vasculitis, aplastic anaemia, polymyositis, Sjogren’s syndrome, one guy with Behcet’s, Reiter’s Syndrome (now known as reactive arthritis, Dr. Reiter was a very bad man) and so on to wonder if an overly active immune system is a good thing.
Other purported benefits of raw milk I have read of include supporting local farming, generally improving vitality, tasting better, and some concept of generally improving karma. Except for the taste, which I am told people can really distinguish (although I’d like to see that myself), I haven’t seen any proof of any of these.
Although milk is a very good food, we were not really designed to drink it as adults. Many people, perhaps the majority worldwide, do not tolerate it well. Even children were not designed to drink cow’s milk. I don’t know many vegans, but those I do know seem to be doing very well, and I have not heard of widespread immune dysfunction in that group. Therefore, if there is a benefit to drinking raw cow’s milk, it must be very small.
Given the known risks, and the hard-to-find benefits, it is hard to see why one would drink raw milk (other than taste).
It intrigues me that when there is a raw milk related disease outbreak, the media is filled with the testimonials of supporters of raw milk. If a bottle of pasteurized milk, from the grocery store, was implicated in such a thing, there would be an immense hue and cry about public safety. This is, to me, evidence of an implicit agreement by the users of raw milk concerning its risks, which may add to its attractiveness for some.
- If you know and are willing to take the risks of drinking raw milk, fine with me. It may qualify you for a Darwin award, but some people like to cliff dive while others like to drink raw milk. We all choose our risks.
- I, and my colleagues, will help bail you out if you lose the gamble, and you will survive—maybe.
- I have concerns about your children. They are not able to truly weigh the risks and do not have the power to make decisions against the wishes of their parents. They also are more ferociously attacked by the pathogens, particularly the E. coli (the condition they get is called hemolytic-uremic syndrome, and it is worse than it sounds, even). To me, it seems morally sketchy to expose them to this unnecessary risk for no proven benefit, but unfortunately, worse things do happen to children in our society.
I would not be surprised to get vehement responses. No death threats, please.