Trans Fats: What They Are, and Why the FDA Is Finally Banning Them

Today, just over 100 years after the advent of trans fats, the FDA has announced that it's taking the first steps toward banning them outright, removing them from the "Generally Recognized As Safe" list and out of the American food supply. It's about time.

Trans fats seemed like such a good idea at the time. Better tasting, better looking, less greasy foods that would last far longer on store shelves, all thanks to the miracle process of hydrogenation and the delicious little trans fats that it produced. At the time, though, we had no clue about the deleterious effects this wonder-ingredient would have on our arteries and cholesterol levels.

According to FDA commissioner Margaret Hamburg, when speaking with USA Today, the FDA is "responding to the fact that the science really demonstrates that trans fat provides no known health benefit and that there really is no safe level of consumption of trans fat." That's about as clear cut as it gets. But now's the perfect time to break down why, exactly, trans fats are such a very bad thing.

Trans Fats: What They Are, and Why the FDA Is Finally Banning Them

So what exactly is trans fat?

Trans fat is most commonly found in partially hydrogenated oils or some shortenings (think Crisco pre-2007). They're the result of the hydrogenation process—bubbling hydrogen through hot vegetable oil to it into a solid at room temperature. The hydrogenation process essentially adds hydrogen to "saturate" unsaturated fat, and break apart its double carbon bonds.

Trans fat has been used in a wide variety of packaged food products including margarine, canned frosting, packaged cookies and cakes, frozen dinners. Since the hydrogenation process made the oil less likely to spoil, trans fats were added to anything that needed to sit on a store shelf for more than three weeks and still be edible.

Trans Fats: What They Are, and Why the FDA Is Finally Banning Them

How is it different from saturated and unsaturated fat?

Good question! Let's take it from the top. You have two types of cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL). LDL is the "bad cholesterol" because it promotes the formation of plaque on your arterial walls. Conversely, HDL is considered the "good cholesterol" because as it floats merrily through your blood stream, it scrapes LDL and plaque off of the walls of your arteries, lowering your risk of heart disease.

Both saturated and unsaturated fat occur naturally in almost every food we eat. Unsaturated fat is typically found in vegetables, avocado, and nuts and are easily identifiable by the presence of double chemical bonds between the carbon atoms. It makes your good cholesterol go up! Saturated fats, on the other hand, are found primarily in meat, dairy, and processed foods, and are held together solely by single bonds. They raise your bad cholesterol, which is why you're so often encouraged to enjoy that bacon and bacon sandwich in moderation.

Saturated fat is bad, yes. But trans fat is even worse. Not only does it increase your LDL cholesterol levels at a far higher rate than either saturated or unsaturated fat, it simultaneously lowers your HDL. No one's exactly sure why—it probably has something to do with trans fats being harder to digest—but the basic point is this: If HDL and LDL are the two sides of the Force, trans fat is Darth Vader and Emperor Palpatine rolled into one.

How did it get to be so popular?

The hydrogenation process was first explored in the late Victorian Era by Nobel laureate Paul Sabatier. Though his work focused on hydrogenating vapors, the discovery gave rise to the margarine, oil hydrogenation, and synthetic methanol industries. This was of significant historical importance because at the turn of the 20th century, America was swimming in soybean oil. Soybeans had just begun being imported as a source of protein for the country's growing population and we had an overabundance of soybean oil byproduct. What we didn't have nearly enough of was butter, but as it turns out, partially hydrogenated soybean oil—aka the world's first margarine—was a pretty close substitute. This gave the technology an immediate market foothold and helped spur further development.

In 1901, German chemist Wilhelm Normann developed a method of hydrogenating liquids, patented the process, and by 1909 was producing 3,000 tons of hydrogenated goods a year at a commercial grade plant in Warrington, England.

That same year, Proctor and Gamble purchased Normann's patent and got into the oil hydrogenation game in a big way. In 1911, P&G unveiled a product that would soon find its way into virtually every pantry in every home, every fast food joint, and every greasy spoon in the country: Crisco. Made from mostly partially hydrogenated cottonseed oil, the vegetable shortening proved itself a culinary superior to lard, though the hundreds of thousands of free cookbooks featuring Crisco-based recipes that P&G gave away didn't hurt either.

Between 1920 and the 1960's America couldn't get enough trans fat. Vegetable shortening had all but replaced lard in Western restaurants and recipes, considered both less expensive than animal product and healthier than saturated fat from butter. It was, in short, everywhere.

But as early as the 1940s, researchers were investigating the physiological effects of trans fat, and by 1956 a growing number of studies suggested that the country's elevated rates of coronary artery disease and its love affair with vegetable shortening might be connected. Because it was 1956, approximately no one cared.

How does it affect my health?

It wasn't for another 40 years that we looked at trans fat with anything other than adoration. But in the 1990s, amid growing concerns of America's still-elevated rates of cardio-pulmonary disease, researchers began to once again study the lipid's effects.

What we found was not good. In 1994, estimates pegged trans fat related deaths in America at just north of 30,000 annually. By 2006 that number had more than tripled to over 100,000 a year. A particularly damning report published in the New England Journal of Medicine that year asserted that "on a per-calorie basis, trans fats appear to increase the risk of CHD [Coronary Heart Disease] more than any other macronutrient, conferring a substantially increased risk at low levels of consumption (1 to 3% of total energy intake)."

A second nail in trans fat's coffin came from a 120,000-member Nurses' Health Study also published in the New England Journal of Medicine that began in 1976 and ran for 14 years. Led by Dr. Frank B. Hu, the team discovered that for every 2 percent increase in trans fat intake relative to total fat (versus carbohydrate intake), a study member's risk for CHD roughly doubled. It would require a 15-percent jump to achieve the same effect when consuming saturated fat. The study found that "the replacement of saturated fat or trans unsaturated fat by cis (unhydrogenated) unsaturated fats was associated with larger reductions in risk than an isocaloric replacement by carbohydrates." In English, trans fat is way super-bad for you.

Trans Fats: What They Are, and Why the FDA Is Finally Banning Them

So is it totally gone now?

With today's announcement by the FDA, we are officially about to end the trans fat era. However, the foundation for this momentous decision was laid a number of years ago.

Over the last decade, as more and more research has found links between trans fat and heart disease, everyone from food manufacturers to fast food restaurant chains have bent over backwards to scrub their menus of anything containing trans fat. Yes, even Crisco. In 2006, the FDA invoked new packaging rules requiring the amount of trans fat be labeled, which further instigated manufacturers to remove the ingredient. Over that time period, American consumption of trans fat declined by more than 80 percent.

With the banning of trans fat, the FDA hopes to prevent 20,000 heart attacks and save 7,000 lives a year, but the ban won't take immediate effect. First the FDA is holding a 60-day review period to collect additional data before making it official. And even then, the manufacturers might have a grace period of up to two years to try to come up with a viable alternative.

Still, the move has been widely lauded by consumer health advocates. "I think it's one of the most important lifesaving actions that the FDA could take," said Michael Jacobson, executive director of the Center for Science in the Public Interest in Washington, D.C. told USA Today.

And while this is indeed a commendable step forward in our nation's health, school picture day may unfortunately never be the same.

Trans Fats: What They Are, and Why the FDA Is Finally Banning Them

[Wiki - Chicago Tribune - Mayo Clinic - USA Today - Web MD - Center for Science in the Public Interest - American Heart Association - Images: AP Images]