Hey, When Raw Milk Data Don't Go Your Way, Try Some Gymnastics, Like CDC Does; Another Look at Harvard Debate
During the raw milk debate at Harvard Law School last Thursday, I criticized our opponents for their failure to present data, as in real understandable numbers.
I had gone to the trouble of analyzing data from official statistics provided by the U.S. Centers for Disease Control--supposedly the gold standard of foodborne illness data. (Some of what I presented was CDC data extracted by the MarlerClark firm, certainly no friend of raw milk.) I found that, over the last decade, between 25 and 175 individuals have been reported ill each year from raw milk. Moreover, I found that the number of illnesses is generally in the vicinity of .5% (one-half of one per cent) of the total number of 23,000-25,000 foodborne illnesses reported each year. (The preceding link goes to the 2008 number, the most recent reported, and that number is down on the order of 1,000 or more from the immediately preceding years.) That's a very small percentage, given that 3% of the population has been found, by the CDC, to be drinking raw milk.
Why wouldn't the opponents comment on the numbers I had compiled from CDC data, or present numbers of their own? For a very good reason. The numbers suggest that because raw milk contributes such a miniscule proportion of all reported foodborne illnesses, it's nothing approaching a significant public health problem.
So what do you do if it gets embarrassing to ignore the numbers? If you're a good bureaucratic number cruncher, you raise a lot of dust and say, "He went thataway!" In other words, you distort and distract, you do anything to avoid discussing the truth.
That is what the CDC did yesterday in publishing a study assessing illnesses from raw and pasteurized dairy over the 14 years of 1993-2006. "Nonpasteurized products caused a disproportionate number (≈150× greater/unit of product consumed) of outbreaks and outbreak-associated illnesses," it concluded in its abstract.
I would be content to ignore these ideologues, except the major media pick up on such pronouncements, coming as they do from the august CDC, the place where all things concerning the science of health are validated. Here's how USA Today led off its article on the study: "Unpasteurized milk, touted as the ultimate health food by some, is 150 times more likely to cause food-borne illness outbreaks than pasteurized milk..."
What's the problem with this "study"? Because the most important number, the number of illnesses, doesn't prove CDC's point that raw milk is terribly dangerous, it pulls the old switcheroo--it focuses on "outbreaks." It's long been known, and acknowledged all around, that there are more raw milk outbreaks than pasteurized milk outbreaks. But when there are pasteurized milk outbreaks, they can be doozies. In the 1980s and 1990s, there were pasteurized milk outbreaks affecting tens of thousands of people. One in 1994 sickened 224,000 people who ate pasteurized-cream ice cream. The true cause was never pinpointed--whether it was the cream or the eggs. That outbreak doesn't seem to have made it into Langer's study. I also don't see mention of a 2006 outbreak in which 1,300 California prisoners were sickened by pasteurized milk.
Indeed, Langer whitewashes illnesses from pasteurized milk--those were flukes, it was the consumer's fault, the food handlers' fault. Excuses, excuses. He says of illnesses from pasteurized milk that "at least 4 (57%) probably resulted from post-pasteurization contamination by an infected food handler. Failure of the consumer to store the dairy product at an appropriate temperature probably contributed to 3 other outbreaks. Such temperature abuse can enable pathogens (present because they either survived pasteurization in low numbers or were introduced after pasteurization) to multiply to concentrations capable of causing illness." I love it. "Temperature abuse." Is that akin child abuse?
The important number--the number of illnesses--is buried deep in the CDC study. That number is 1,571 illnesses attributed to raw dairy over the 14 years of the study. It works out to an average of 112 per year. As I said, there are between 25 and 175 reported illnesses each year.
I actually wrote about the lead author, Adam Langer, a few years ago, when he came up with this truly perceptive insight: In states that prohibit raw milk, there are fewer illnesses from raw milk than in states that allow raw milk. As I wrote at the time, you'd likely have the same phenomenon with any foods--ban deli meats in one state and you'll have fewer illnesses from deli meats than in another state where they're allowed. This bizarre insight is one of Langer's key conclusions for this latest paper.
It's supposed to be about safety, but we see yet again that it's really about politics and propaganda. Don't know why I'm always surprised. Guess I just had it drilled into me too many times that the CDC cares about the science.
The Boston Globe has a nice wrapup of last week's raw milk debate. It doesn't take a stand, just reports the facts, along with good atmosphere and nice photos.