In 1961, the American Heart Association (AHA) published a study that would eventually come to define American attitudes toward cholesterol. The diet-conscious public learned that cholesterol was a fatty substance found in the blood, which, if consumed in excess, could lead to the ugly consequences of coronary artery disease, atherosclerosis, and heart attack. It was, in effect, the enemy.

Foods like butter, cheese, and eggs felt the warnings in full force. Data from the U.S. Department of Agriculture show egg consumption has fallen nearly every year between 1945, when people ate an average of 421.4 eggs annually, and 2010, when they ate fewer than 250. The best estimates suggest waning interest in eggs and other fats can be traced back to the initial set of mid-20th century guidelines. Since then, few pieces of evidence have been strong enough to overturn public perception. But new recommendations from the federal Dietary Guidelines Advisory Committee suggest the antiquated rules aren’t just misguided. They could be flat-out wrong.

Talking to CNBC, chairman of cardiovascular medicine at Cleveland Clinic Steve Nissen called the reversal the “right decision.” For years, he said, “we got the dietary guidelines wrong. They've been wrong for decades.”

By and large, science has wised up in the 54 years since the AHA’s report. We’ve learned that cholesterol, which comes in two flavors — high-density and low-density lipoprotein, or so-called “good” and “bad” cholesterol — is actually essential to many bodily processes, helping to stabilize cell membranes and synthesize bile acids and vitamin D. In the coming weeks, the committee’s final report will bring to light several misconceptions about cholesterol. Chief among those are the risks people face depending on their overall health.

In years past, people were broadly warned against consuming more than 300 milligrams of cholesterol on a daily basis. That is roughly the equivalent of one egg. The new guidelines suggest only people with preexisting conditions, like diabetes or genetically high cholesterol, should worry about the cholesterol in their food raising the cholesterol levels in their blood.

The new Dietary Guidelines, which get released every five years, will also tackle consumption levels of salt, sugar, red meat, saturated fat, and omega-3 fats. While some experts praise this specificity, which will recommend intake levels down to the milligram, others seem wary the new approach conceals an ongoing controversy in food science.

"Almost every single nutrient imaginable has peer-reviewed publications associating it with almost any outcome," John P.A. Ioannidis, a Stanford University professor of medicine and statistics and critic of nutritional science, wrote in a 2013 editorial for the British Medical Journal. "In this literature of epidemic proportions, how many results are correct?"

In the decades since the AHA’s recommendations, another trend has emerged: statins, which may partly underlie the committee’s new suggestions. Cholesterol medication is so common among older Americans, taking it almost seems guaranteed. In 1988, roughly two percent of Americans over the age of 45 took statins. By 2008, that rate had jumped to 25 percent. Some have even made the leap to arguing everyone over 50 should take statins, despite the risk of heart attack in people who would otherwise derive no benefit from them.

If anything, the new guidelines may finally help curtail the growing obesity epidemic in the U.S. Steve Nissen believes the move toward sugar and carbohydrates, and the subsequent boom in diabetes that followed, stems from Americans’ fears about fat. In reality, he says, the solution may have been more dangerous than the problem ever was.