Here are five myths about bacon, our newly-maligned national culinary pastime, which author Mark Essig tries to clear up. (The Washington Post)

When the World Health Organization this past week linked consumption of processed meats to cancer, most of the articles bearing the bad news were illustrated with images of bacon — the meat product, apparently, that Americans hold most dear. Threat of premature death might put us off hot dogs or ham. But bacon? You can pry it from our cold, greasy fingers. The adoration, however, is often plagued by misinformation and wishful thinking. Here are five myths about this newly maligned national culinary pastime.

1. Bacon is delicious.

Well, it is now. The twin pairing of salt and smoke, fat and meat cannot be equaled. But there are those who’ll tell you that it’s “impossible to have terrible bacon.” They’re just as wrong as those who claim there is no such thing as bad sex or bad pizza. Historically speaking, there has been far more bad bacon than good bacon. That’s because bacon, though now a cult food, once served as a survival ration. It was peasant fare, as suggested in Shakespeare’s “Henry IV,” only fit for “bacon-fed knaves.”

Nowadays we kill ourselves by overeating, but until a couple of hundred years ago, starvation posed a far more serious threat, as most people lived on grains and struggled to acquire protein and fat. In many places — from China to Central Europe to North America — pigs offered the cheapest source of meat available.

This was true in England in 1100 and in Iowa in 1800. Until the 1950s, we ate more pork than beef, and most of it was cured at home and stored under questionable conditions. In other words, it probably wasn’t delicious in the least. When Frederick Law Olmsted, then a journalist, journeyed through the South in the 1850s, he griped that “the bane of my life” was a steady diet of “corn-bread and bacon.” It was virtually all he ate during his six-month trip and in no way a special treat. Today’s bacon mania would have puzzled him.

2. Bacon is belly meat.

Bacon is “cured meat from the sides and belly of a pig” — at least that’s Google’s definition. Describing pork bellies as a traded commodity, Investopedia says bellies are “also known as bacon.” But Canadians make bacon from pork loin, a lean, cylindrical muscle; a slice is round and nearly fat-free. English bacon is the loin with an extra wedge of meat and fat attached; a slice is shaped a bit like a comet with a tail. Only in the United States does bacon refer exclusively to pork belly.

Considering that the words “bacon” and “back” share a linguistic root — and that the loin muscle runs along a pig’s spine — English and Canadian bacon win the award for etymological accuracy.

But before the Civil War, bacon, in this country, referred not to a part of the pig but to a curing technique. Any meat that had been dry-cured with salt and smoke — rather than soaked in brine — was called bacon. A visitor to the Illinois prairie in 1831 noted that the pioneers “make bacon of hams shoulders and middlings.” The cut didn’t matter; the preparation did.

By the 1870s, Chicago’s meat-processing plants were butchering more than 1 million hogs a year. Packers began grading pork based on quality (“prime,” “mess” or “clear”) and standardized the names of cuts. And at some point along the way, the term “bacon” became synonymous with belly meat. Sometimes the packers dry-cured this bacon in the traditional way, but the process took more than a month. By the 1910s, they had turned to wet curing because it could be accomplished in days, resulting in an inferior product but a quicker return on investment. The industry wiped away the established definitions of bacon — first as loin or back meat, then as dry-cured meat — and gave us the wet-cured belly we know as bacon today.

3. Bacon has always been what’s for breakfast.

Bloomberg Business’s David Sax observes that bacon has “moved from a breakfast meat to a food trend touching an incredible array of consumer goods, both edible and not, from bacon-heavy fast-food burgers and bacon-infused desserts at fine dining restaurants to bottles of bacon-distilled vodka.” Bacon, though, wasn’t always a ubiquitous breakfast option. Before 1900, most Americans ate meat-heavy breakfasts. But by the 1920s, many urbanites had turned to simpler fare. Meatpackers complained that too many Americans, especially office workers, had shifted to corn flakes and other grain-based breakfasts.

Frequently, marketing icon Edward Bernays gets credit for convincing consumers that “bacon and eggs was the true all-American breakfast,” as NPR put it, on behalf of the Beech-Nut meatpacking company — though that claim, too, is at least partly a result of marketing.

Credit, as Roger Horowitz notes in “Putting Meat on the American Table,” certainly goes to developments during the years after World War II, when pork packers automated production lines so that bellies were compressed to uniform thickness, needle-injected with brine, machine-sliced, shuffled into a shingle-like display and packed in clear plastic that let customers admire the streaks of lean and fat. The first such packages, made with cellophane in the 1920s, didn’t keep the meat from becoming discolored. Only vacuum-sealing and new materials such as PVC, developed later, gave sliced bacon the shelf life needed to create tempting displays in supermarket cases.

By the 1960s, 60 percent of American families bought bacon, and in a reversal of traditional dining patterns, wealthier families were now more likely than poor ones to have it on the table. Aided by a strong industry marketing push, bacon shed its reputation as a country staple and was reborn nationwide as a breakfast side enjoyed by all social strata.

4. Uncured bacon is nitrate-free.

Since the Middle Ages, bacon has been cured with nitrates. This was originally accomplished using salt and smoke, but saltpeter, a.k.a. potassium nitrate, was eventually introduced. When they come into contact with bacteria, nitrates break down into nitrites and add a distinctive flavor and a pinkish hue, a far more appetizing color than the dull gray that cured meat would otherwise be. Most important, they kill the pathogens that cause botulism. But consuming nitrates, the Mayo Clinic tells us, “could increase your heart disease risk.” No one wants that, and for years it’s been one reason we’ve been warned off of cured meats. As a workaround, some brands offer “uncured” “nitrate-free” or “nitrite-free” bacon.

Except those products typically contain celery powder — which, of course, sounds harmless. But like a number of vegetables, celery contains naturally occurring nitrates, and here they serve the same purpose as the synthetic stuff, meaning uncured or nitrate-free bacon can actually have as many nitrates and nitrites as the standard kind.

5. Eating bacon is as risky as smoking.

Nitrites, whether synthesized or derived from celery, are indeed cause for concern. In the body, they can transform into what are known as N-nitroso compounds, which have been linked to bowel cancer. That’s why the World Health Organization this past week added cured meats to its list of carcinogens.

But when the Guardian reports this news with the headline “Processed meats pose same cancer risk as smoking and asbestos, reports say,” it’s hogwash.

The WHO placed smoking, asbestos and processed meats in the same category because all have solid links to cancer. But that doesn’t mean they have the same level of risk. As Wired explained, “Smoking increases your relative risk of lung cancer by 2,500 percent; eating two slices of bacon a day increases your relative risk for colorectal cancer by 18 percent.”

Twitter: @mark_essig

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