There’s an apocryphal story about Clarence Darrow’s early career that goes something like this:

A man was on trial for biting another man’s ear off in a fight. Darrow was interviewing a witness to the incident, and asked, “Did you see the defendant bite off the plaintiff’s ear?”

“No, I didn’t,” was the reply. Darrow, a young lawyer at the time, didn’t know when to leave well enough alone – after all, he’d made the point – and went on for the dramatic finish.

“Well, then, sir, how did you draw the conclusion that the defendant committed the crime of biting off the plaintiff’s ear?”

“I saw him spit it out,” came the laconic answer, turning a slam-dunk to a rim shot.

What does this have to do with food safety? By example, rather a lot. Take my earlier post on mercury in fish. Researchers can measure mercury in albacore and other fish till the sardines come home, but if they’re not measuring the selenium in the same fish – which binds the mercury safely – they’re not telling the whole story. All we hear is, “Step away from the tuna, it’s got mercury in it” not, “Dig into that albacore, it’s got so much more selenium than it does mercury and it’s way good for you, too!”

Dramatic headlines often mask half-truths
This same willingness to make pronouncements on the basis of limited, or even more common, misinterpreted information seems to pervade the media and what passes for health wisdom. Sure, it’s a lot easier to get eyeballs on a dramatic headline that says (as many did in 2007), High Intake of Cholesterol May Lead to Greater Risk of Breast Cancer, but personally, I wouldn’t plan dinner around it without knowing more. In the case of the fat + cholesterol = breast cancer diet scare, of course, there were a slew of murky little details that got left out of the reporting. (Don’t bore readers with details.) The study was based on mice fed two diets: a more-or-less standard rat chow or what was blithely referred to as a “high-fat Westernized diet.” The latter was nearly half sugar of various kinds, some milk protein, about 20 percent milk fat, and a little cellulose. Yep, sounds familiar – just like what I had for dinner yesterday! Given the fact that there is some evidence on the books that sugar consumption promotes tumor growth, as well as the fact that 20 percent fat is something most diets aspire to, this study hardly implicates fat as a risk factor. (Check out the excellent Mark’s Daily Apple analysis of the study for more detail – it’s an excellent reminder of just how lame so much mainstream medical reporting can be.)

The cult of the new (and the incredible edible egg)
In our enthusiasm for New!, More Scientific!, Better! information, we have let our collective memories lapse and put our faith in what we see this very day/hour/minute in print, whether digital or physical – preferably from someone with letters after their name to validate the fact that They Know More Than We Do. This isn’t all that earth-shattering a concept; I’ve heard it called “The Cult of the New,” which is apt.

But it does represent a problem for us when we take the shiny New! information and let it crowd out some perfectly valid knowledge from an earlier time, or when we let it push logic out the window. Do you know why you’re only supposed to eat eggs that have been cooked to rubbery tastelessness? Well, we “know” that you can get salmonella if you don’t. But why is that? I used to eat cookie dough, and recipes for mayonnaise and Caesar salad called for raw yolks till fairly recently.

Something must have changed. And it isn’t that we just got smarter in the last couple of decades.

What changed was the way eggs are produced. Eggs used to come from local farms. The chickens ran around on the ground, getting lots of sunshine, pecking at bugs, scratching in the dirt, taking dust baths, and laying eggs in brooding boxes. It takes land to do this, because you need to allow 20 or 30 yards per chicken for them to graze and scratch. This  kept flocks smaller. But then, in the 1930s, innovation! If chickens live off the ground, on mesh floors, their manure drops through the floor and you have to clean less (a conveyor belt takes the poop away, how modern). More innovation led to stacks of chicken cages so that one could raise a lot more chickens in a lot less space. Of course, these “battery” systems meant that the chickens would never scratch, dust-bathe, peck, or get sunshine. And a whole host of other ills for the chickens followed, like low light to keep them calmer, trimming their beaks to keep them from pecking at one another, and so on.

Between the mid-40s and the mid-90s, egg-laying chickens kept in battery cages went from less than 50 percent to over 90 percent. Flock sizes went from a few thousand to several thousand to 80,000 over the same time. And there were more and more warnings issued about the risks of raw or soft cooked eggs.

So that collective memory lapse affected both the farmers (who didn’t want to be seen as backwards by continuing to raise their chickens on the ground, and who made less money if they did) and the buying public (who forgot what eggs really looked and tasted like). And medical wisdom kept pace, by solemnly telling the public that raw eggs were risky.

Battery eggs can constitute a health risk, not just from crowding (though that’s a big issue) but all too often from filth. Remember the cautionary tale of Jack DeCoster’s egg businesses, with half a billion eggs recalled in 2010 because they were making people sick. I’d recommend not just cooking those eggs to death, I’d recommend not buying them in the first place!

But because it’s assumed that you’ll be eating eggs from chickens raised in battery cages – after all, over 90 percent of all supermarket eggs still are – the caution has spread to all eggs, regardless of origin. I guess it’s assumed that we’re too dumb to distinguish between organic, free-range eggs, in which the incidence of any salmonella at all is less than 5 percent (according to a large-scale British study), and battery eggs, in which the incidence of salmonella is over 23 percent (same study; it showed that the larger the farm, the higher the incidence of salmonella contamination). Should you have a source of locally raised, pastured poultry, the incidence drops to nearly nothing.

Muddying the waters a bit more is a study conducted by the Centers for Disease Control (CDC), which demonstrated that most of the actual illness from salmonella may well come not from the eggs, but from cross-contamination at home.

The beat goes on
I’ve gone into some detail on eggs because they’re such a high-profile food, and one in which the belief about the associated risks is such conventional wisdom. But this same pattern has been repeated across the food and agriculture landscape, from beef to peanut butter, from salmon to romaine. It looks something like this:

• An industrial change in the way a traditional food is grown or raised;
• Widespread adoption of the new growing method over time;
• Development of health issues associated with the food grown in the new way;
• Public health guidelines developed and promoted to address the new health issues;
• Assumption that the food was never safe in the first place.

What does all this mean for us? A misplaced trust in the institutions that promise us that they will keep our food safe (using methods that a) would not be necessary if the food was safely produced in the first place or b) that further damage the food, rendering it practically useless to our bodies). A deep-seated distrust of the food we eat, approaching obsession for some. An industry built around transforming formerly healthy, delicious foods into sterile, tasteless calorie-and-nutrition delivery units.

I don’t think that this represents the best that science, public health, or agriculture has to offer us. And turning this ship around, large and dominant as it is, is a huge, complex issue, to say the least. But I – and you, gentle reader – can make different choices for ourselves, by supporting farms and food producers who grow, raise, and prepare foods that retain their original qualities and nutrients. We can also develop our critical thinking. The next time you see a breathless headline, or interview with a noted physician on the news, about the relationship of food A to disease B, or about what you should avoid or include in your diet to be healthy, I hope you’ll take a deeper look. (What I do these days when I see such a headline or interview is assume that the opposite is probably true and proceed accordingly – but that’s just me being contrary.)

So follow the model of the young Darrow, and keep asking questions all the way to the end. The headline-grabbing talking heads may lose the trial, but you’ll gain a greater understanding of what constitutes real food safety.