Imagine for a moment that sales of luncheon meats like salami, bologna and hot dogs were prohibited in half the states beginning in 1993, because such products cause more than 6,000 illnesses each year (see page 13 of the publication, which is actually about illnesses in a different year–this is hypothetical, remember).

Now imagine, 15 years later, you are studying data from 1993 to 2006 on the number of illnesses from luncheon meats in all 50 states.

In which states would you expect to have the most cases of foodborne illness caused by luncheon meats—the ones in which sales were illegal, or the ones in which sales were permitted?

This is not supposed to be a trick question. At least I haven’t been able to determine the trick, because I’ve been thinking about it for the last six days, since that raw milk symposium outside Washington last Tuesday, sponsored by the International Association for Food Protection, and couldn’t find anything overtly tricky.

My answer is always the same: the states that prohibit luncheon meats would have fewer outbreaks of illness  because, well, there’d be less bologna, salami, and hot dogs available for sale than in the states where it was legal. And then I wonder, once again, am I missing something here?

The reason I’ve been agonizing so much about this question is that there was a lengthy presentation about a recently concluded (and as-yet unpublished) study from a highly regarded scientist from the U.S. Centers for Disease Control. The title of the presentation was this: “Do State Raw Milk Sales Restrictions Reduce Raw Milk Outbreaks: A Policy Analysis”.

The scientist, Adam J. Langer, analyzed data on foodborne illness from states where raw milk is illegal, and compared it to states where it is legal. As you can see from his PowerPoint presentation, his slides are very colorful, and he’s got assessments of illnesses per “billion person-years” and “incident density ratios.” He did a lot of work on this baby.

And guess what? According to Langer, “If you live in a state that permits raw milk sales, you have two to three times the risk of having an outbreak” than if you live in a state where it’s prohibited. Of course, that then becomes fodder to trash raw milk, to warn of “an increased risk throughout the country” if Rep. Ron Paul’s legislative attempt to lift the federal ban on interstate sales of raw milk were to succeed.

Just another CDC scientific breakthrough, I guess. Doing the hard work and digging that needs doing to help us better understand the dangers of raw milk. Or is it a trick question?