By 1976, the president of Tufts University, Jean Mayer, was labeling salt "the most dangerous food additive of all." The U.S. Senate was recommending that Americans reduce the salt in their diets by as much as 85 percent. The New York Times was blaming salt for "high blood pressure, heart and kidney disease, and stroke." Salt apparently wasn't satisfied with some measly high blood pressure -- it had become food evil incarnate, haunting our entire freaking anatomy.

There was just one slight problem. You see, in order to induce high blood pressure in those aforementioned rats, Dahl had pumped them full of ... hang on, let us grab our calculator real quick ... almost 15,000 percent more sodium than the average American's consumption. Countless more recent studies have utterly failed to back up the relationship between salt intake and high blood pressure. Not only that, but it turns out that we actually need salt to, you know, live. Mothers unnecessarily restricting the salt intake of their young children have even sent them into shock or, holy shit, outright killed them.

Photodisc/Photodisc/Getty Images
"Please, just a Ramen seasoning packet. It can be my birthday and Christmas gift this year."

The truth is that science is still trying to figure out what causes high blood pressure -- maybe it is salt for some people, or just certain types of salt. But there's a reason we get a new "stop eating ________!" warning every few years or so -- food science is complicated as shit. It's hard to figure out what problems are caused by diet versus genetics, or any of the billion other environmental factors that can slowly murder you behind your back. And the biggest mistake you can make is to declare one part of your diet to be The Bad Guy and just ignore everything else.

Want another example?

The Misconception:

What salt is to high blood pressure, saturated fat is to heart disease. Every overweight American (that is, every American) has a recurring nightmare in which saturated fat is an evil, anthropomorphized blob squelching its way down the hallways of our arteries, slowly choking off the flow of our precious lifeblood, and growing ever larger and stronger with each and every visit to the KFC.

But why not simply stop visiting the KFC, you ask? Because we cannot stop visiting the KFC. (Thus, "nightmare.")

arselozgurdal/iStock/Getty Images
It's a vicious cycle.

But, again, it turns out saturated fat was convicted on some pretty shaky evidence.

The Guy You Can Thank for It:

Ancel Keys.

Back in the 1950s, America found itself facing a shiny new epidemic: heart disease. A rarity in the decades before, suddenly people everywhere were clutching their chests and dramatically exclaiming This is The Big One, Elizabeth! I'm coming to join ya, honey!" before keeling over left and right.

william87/iStock/Getty Images
"Quick! Eat some fat to lubricate your arteries!"

Possibly related to this phenomenon was the fact that literally everyone smoked. But Keys, a physiologist at the University of Minnesota in Minneapolis, wasn't one to look for easy answers. Instead, he examined a few hundred middle-aged businessmen and found high levels of cholesterol in their blood. He published these findings along with his famous "Seven Countries" study, a wide-scale examination of diets all over the world, showcasing the "Mediterranean diet" as the ideal, low-fat way to avoid cholesterol and live a life free from heart disease.

Lipophobia -- the fear of dietary fat -- was born. Throughout the 1980s, everyone from the American Heart Association to the surgeon general was forcibly hammering the idea of a low-fat diet into the public consciousness. It wasn't until 2002 that someone took a closer look at Keys' famed studies and found that he had only examined the diets of countries that were likely to back up his preferred hypothesis.

Jack Hollingsworth/Photodisc/Getty Images
"In Chart 4, you can see that most of Soviet citizens died of "too much happiness," and they barely ate anything!"

For instance, the main focus of the study was Crete, a place full of "islanders who tilled their fields well into old age and who appeared to eat very little meat or cheese." Completely absent were European countries where the population practically bathed in dietary fat, yet were relatively heart disease-free. Not surprisingly, more recent studies quite simply do not back him up. As recently as March of 2014, researchers examined the results of 72 studies that explored the connection between fatty acids and heart disease and "found no significant evidence that saturated fats increase the risk of heart disease."

Again, we're not saying that this gives you a free license to switch to an entirely deep-fried diet. But declaring this one kind of bad food to be the lethal boogeyman convinced a whole bunch of people to substitute shit that can be even worse -- foods full of sugar and/or carbohydrates, consumed in quantities our poor bodies had never seen before. We're not fancy food doctors or anything, but it almost seems like the real villain is our utter inability to do anything in moderation. "All right, science, I've got a huge box of doughnuts in one hand, and a bucket of bacon in the other. Tell me which one is healthy!"

svengine/iStock/Getty Images
"I'll drink this oil drum of Diet Coke while you decide."

And while we're on the subject ...

Hell, it's almost too good to be true -- all you need to do is swallow some little golden oil capsules from the supermarket and listen to your heart let out a joyous laugh.* But, if it sounds too good to be true ...

*Figuratively. If this actually happens, get to an emergency room immediately

The Guy You Can Thank for It:

Jorn Dyerberg.

Back in the 1970s, this Danish chemist talked his pal, the awesomely named Hans Olaf Bang, into suiting up in the most offensive furs they could muster and traveling to the icy North to study the diets of the Inuit population. As a result of their findings, Dyerberg published the "Eskimo diet," claiming that the fish-heavy diet of the Inuit directly resulted in their extremely low rates of heart disease.

Wikipedia
"Your mother and I have had this diet our whole lives and we're just fine. Now eat it, or you won't get any akutaq!"

Little did the researchers know that they had just given birth to the omega-3 craze and what today is a billion-dollar fish oil supplement industry. But, as you should expect by this point in the article, there was a problem. These men were nutritionists, not cardiologists, and they relied solely on death certificates to tally up the number of Inuit deaths resulting from heart disease (answer: almost none). But that method was about as reliable as a survey on the current state of race relations conducted via Xbox Live -- seeing as how most of the population lived in very remote areas with no medical personnel, by the time someone finally got around to filling out a death certificate, they were likely to list the cause of death as "um, death, I guess."

In subsequent studies, the connection between fish oil and heart disease has been tenuous at best. And there won't be a definitive answer until 2018, when current randomized trials are completed. Now, it's important to note that fish oil isn't bad or anything -- scientists are fairly certain that consuming it, at least in the natural way (you know, eating fish), is good for you. But for all the shoddy evidence that Dyerberg and Bang based their assumptions on, they could've been unknowingly effecting a wide-scale transmogrification into a race of Aquamen.

Jorn Dyberg via University of Copenhagen
"That definitely wasn't our plan all along or anything ..."

And speaking of mutated horrors ...

Actually, that description is being way too generous -- most of his "research" is based on his own personal observations and anecdotal evidence, meaning that the good doctor claims to have personally observed dramatic improvements in his patient population after putting them on a diet of his own design (now available for the low, low price of $16.99). Seems legit.

The wonky lynchpin of Davis' theory is that when a person digests wheat, a specific variety of peptide is produced. These wheat peptides then interact with the body's opioid receptors (the same receptors that narcotics bind to), turning us all into honest-to-goodness wheat junkies. And, no different from when a human body becomes addicted to more nefarious substances, a veritable cascade of unhealthiness ensues.

Purestock/Purestock/Getty Images
"It's like a Rube Goldberg device that ends with you dying."

Now, to be fair, in an article published in Cereal Foods World, Dr. Julie Jones compared his claims against currently available scientific data and found that about half of what he says is pretty much spot-on. Unfortunately, it's the more fantastical half that Dr. Davis yanked straight out of his wheat-free (and, as a result, admittedly svelte) rear end.

And while we're on the subject of diet advice you got from your yoga instructor ...