I know that I've been slacking the last few weeks. When I began this blog, I swore up and down that I'd post every two nights, but I got to feeling like that was too frequent. I was wearing out my four readers with the overload of fascinating information I was pulling together. So I decided to go down to three. That worked for a few weeks... But, you see, I have a lot going on right now, and this week I actually went four days without posting (gasp!) SO... hoping to recapture my lost reader, I'm going for the gusto, I'm finally going to resume discussing my agonizing dilemma over whether or not to get a raw milk share (see Where to Start Looking for Raw Milk).
Why, you might ask, did I wait so long? I do have a good excuse. There is so much information out there on this topic, that I couldn't figure out how to assemble it. I've read presentations, infectious disease articles, FDA warnings, watched California senate debates, and after all of this, I still can't make my mind up.
But I do feel that I've boiled it down to a few key questions...
Does raw milk carry more dangerous pathogens than pasteurized milk?
How this question has been answered is actually quite interesting in itself. The pro-raw milk articles I've read point out that in the numerous tests that have been done comparing pathogen levels of raw and pasteurized milk, the milk is usually compared from the same source.
In fact, in one study, the cows' udders were injected with bacteria to see if the bacteria was passed into the milk, which it was (shoot, sorry, I can't find my reference on this - but I know I read it somewhere). This sounds like a logical test, except that it only tells us one thing - milk with a high pathogen level will have a reduced pathogen level after pasteurization.
What if the pathogen level of the milk isn't high to begin with? What I'm getting at is, have any studies been done examining the pathogen levels of milk from pastured, grass fed cows? None that I could find, unfortunately. I am trying to be unbiased here, but I do strongly believe that cows raised on grass and fresh air are going to be infinitely healthier than industrial dairy cows crammed together in a building eating corn meal and antibiotics. Healthier cows probably produce cleaner milk. For instance, "Vitamin E and selenium improve immune cell function and allow proper closing of the streak canal after milking, the canal through which pathogens generally infect the mammary gland ... Vitamin E intakes of lactating cows on pasture can be four to five times higher than the average intake in the United States"^
If the cow tested in the previously mentioned study is a healthy pastured cow that does indeed deliver infected milk after her udder is injected with bacteria, but is otherwise uninfected, what does the study prove?
A more relevant study would probably be to test the infection rates of raw milk in pastured cows.
A follow-up question I have is how clean does pasteurized milk stay after pasteurization? I'm curious as to whether killing off all bacteria in milk is really a good thing - couldn't we be creating the perfect environment in which bacteria that survives pasteurization or finds its way into the milk could thrive, similar to the Superbug effect that the overuse of antibiotics has caused in humans? Statistics on rates of disease caused by pasteurized versus raw milk would probably help answer this question. So...
Is the risk of getting sick higher with raw or pasteurized milk?
Here are some interesting statistics from the Weston A. Price article, RESPONSE TO ANTI-RAW MILK ARTICLE Published in Clinical Infectious Diseases, January 2009
Statistics from the FDA attribute a 25 fold decrease in the % of foodborne illnesses due to milk since 1938 to pasteurization, but the source of the improvement cannot be isolated as states adopted many other cleanliness standards at the same time as they adopted the pasteurization standard.
These numbers bring up a strong point in favor of eating local milk, pasteurized or not. Listening to the news the last few years, I can think of so many stories related to massive disease outbreaks attributed to one initial source: spinach, tomatoes, peanuts. These infections were probably not widespread to start with, but there seems to be so much consolidation in the food industry that a small outbreak can reach many, many people. This phenomenon would explain why even if pasteurized milk is safer than raw milk, the fact that it is usually produced on a large scale by industrial dairies means that it has the potential to infect many, many more people. A local dairy has a much smaller sphere of influence.
I felt that The Infectious Diseases article being rebuked by the stats just above, Unpasteurized Milk: A Continued Public Health Threat, did not seem very objective. It seemed to me to throw out common raw milk scare tactics, salmonella, E. Coli, Listeria, without discussing them in very scientific terms. Here is an example of one study:
"An overwhelming majority of dairy producers feel responsible for the safety and wholesomeness of the food products that leave their farms. Good animal health and hygienic conditions on the farm are important for the welfare of the animals and the profitability of the producers, as well as for the quality and wholesomeness of the raw food products leaving the farms for human consumption. Nevertheless, many dairy producers are unaware of the zoonotic potential of the most common bacterial contaminants in milk. In a recent mail‐based survey of 461 Ohio dairy farm respondants, 36% did not think Salmonella species caused disease in humans. Likewise, 81%, 88%, and 91% of farmers indicated that Listeria, Cryptosporidium, and Campylobacter species, respectively, were not associated with disease in humans (J.T.L., unpublished data)." I'm sorry, but I do not find that to be a particularly compelling statistic. I can see why we would like a dairy farmer to understand the link between food poisoning and the hygiene standards he or she follows, but I'd bet there are plenty of passionate, humane, clean dairy farmers that don't.
I have primarily referenced two articles above, but I did read a few more, and felt that the two sides of the argument were roughly the same.
To me the core of the debate seems to be this
- Pasteurized milk probably does kill some dangerous bacteria. Does this benefit last until the milk reaches your table, or is there potential for subsequent infection due to the now nearly sterile environment created by pasteurization?
- Has pasteurization actually made milk safer, or is it just part of a general improvement in industrial dairy cleanliness standards?
- Is milk from cows raised on pasture safer than milk from industrial cows, regardless of pasteurization?
- If raw milk has a higher potential for infection, but pasteurized milk infections reach more people, from a statistical point of view, which one is really safer?
For my part, I've made up my mind that if I am to drink raw milk, it will have to come from cows that are 100% grass fed and free range. I believe this gives me the best chance of avoiding the higher infection risk of raw milk, if indeed there is one. This means that I'll probably need to check it out myself to be sure.
Is raw milk more nutritionally complete than pasteurized milk?
Phew, more on this another time.