Partially Hydrogenated Oils

“…we estimate conservatively that 30,000 premature deaths per year in the United States are attributable to consumption of trans fatty acids.”
                                                                                         - A. Ascherio and W.C. Willett
                                                                                            Department of Nutrition,
                                                                                            Harvard School of Public Health

Next time you’re eating a candy bar, a cracker, a cookie, a piece of bread, or a granola bar, look on the list of ingredients and see if it includes partially hydrogenated oil. Chances are very high that it will. If you want to reduce your risk for heart disease, cancer, Alzheimer’s, diabetes, and even blindness, you’ll quit eating this substance now.

What Are Partially Hydrogenated Fats?

Partially hydrogenated fats first appeared on the market in the early 1900’s in products like Crisco and margarine, as an inexpensive substitute for butter. Today it is used in everything from cookies, to bread, ice cream, French fries, and peanut butter. Its main appeal to food manufacturers is its stability, meaning it can stay on the shelf for a long time before the fats start to go rancid.

Fats are made of long chains of carbon atoms connected together, with hydrogen atoms sticking off the sides. They look something like this-

  - Saturated Fat

The above fat is considered “saturated”, because all the Carbons have Hydrogens attached to their sides. If a hydrogen is missing, the fat is considered “unsaturated”, and there is a double-bond between the carbons. Polyunsaturated just means that there is more than one double bond.

  - Polyunsaturated Fat

A hydrogenated fat is a polyunsaturated fat that has been reacted with hydrogen at a high pressure and temperature for 6 to 8 hours. The result is the breaking of double bonds and attachment of hydrogen to some of these bonds. Thus, the unsaturated fat becomes a saturated fat. Because totally hydrogenated fat is hard and crumbly, food manufacturers use partially hydrogenated fat, in which some double bonds are not hydrogenated.

Trans-fats

Looking at the picture of polyunsaturated fat above, you can see that both carbons are on the same side of the carbon chain at each double bond. This is called a “cis” configuration, and is the way that unsaturated fats are found in nature. Hydrogenation produces dozens of strange-looking fats. The most abundant products are called trans-fatty acids. Trans-fatty acids are molecules that are in the “trans” configuration in which hydrogen molecules are now on opposite sides of the double bond. The average hydrogenated fat is composed of 20 – 40% trans-fats. Thus, most people are consuming several grams per day of a molecule that is totally new to human physiology, making it the most abundant food additive in the American diet.

So what?

The fats we eat make up the membrane of every cell in our body. If we eat olive oil, our membranes will be made up of the kinds of fat found in olive oil, and if we eat Crisco, our cell membranes will be made of Crisco. The body has the ability to take apart and rearrange most of the molecules that we ingest in the food we eat, using them for energy, various reactions, and to build the structure of the cells and matrix that makes up the body. It is not, however, able to change a trans-fat into a cis-fat.

The cell membrane determines what can move in and out of the cell, and is involved in processes that affect how almost every aspect of the body works, from hormone signaling to how our cells communicate with each other. If we build our body with trans-fats from partially hydrogenated soybean oil, we will be using building blocks that don’t quite fit.

Effects on Health

By the early 1970’s, many researchers had begun to suspect that hydrogenated fats were having a negative effect on the human body. This idea was ferociously opposed by the food manufacturing industry (including the Margarine Manufacturers Association, the Grocery Manufacturers Association, and the International Food Information Council), and the politics of medicine, food production, and government regulation managed to keep this idea out of the public consciousness for quite some while. Fortunately, science is prevailing over politics, and the truth is finally coming out.

Studies now show that trans-fats lower HDL (“good”) cholesterol and raise LDL (“bad”) cholesterol more than any other food in existence, and increase blood triglyceride levels as well, dramatically increasing the risk of cardiovascular disease. A study of 700 European women suggests a 40% higher risk of breast cancer in those with high consumption of hydrogenated fats. A study that was recently published in The American Journal of Clinical Nutrition finds a significant increase in the risk of diabetes in those that consume trans-fats. Other studies show decreases in testosterone, lower birth rates, and altered liver enzyme activity, and even increased risk of macular degeneration, the most common form of blindness among the elderly. It is also suspected that trans-fats interfere with the production of hormone-like molecules called prostaglandins. Made from fatty acids, these are substances that among other things help regulate blood pressure, kidney function, inflammation, and the immune system.

It’s not surprising that trans-fats can cause so many problems in the body. Almost all reactions that occur in the body are catalyzed by enzymes, and these enzymes can normally only react with a certain kind of molecule. So if you’ve got a misshapen fat molecule in your cell membrane, it is probably interfering with essential reactions that would normally take place in a “cis” fatty acid. In other words, because the hydrogen atoms are on opposite sides of the double bond, the enzyme can only “half-fit” onto the molecule, leaving it unable to properly perform its function.

In November 1999, the FDA issued a new rule proposal that would require trans-fatty acids to be listed on food labels as a subset of the saturated fat content. This information will begin appearing on food labels in the next two years.

Looking Out For Number One

The best way to increase the odds of a long healthy life is to be pro-active. It is much easier to prevent heart disease, cancer, and other degenerative diseases than to cure them once they occur. The growth, manufacture, and production of food products is a huge industry, and powerful economic interests are involved. So it is essential that you educate yourself. If you want to limit or eliminate your intake of hydrogenated fats, the first step is to become a habitual label reader, and choose foods without hydrogenated fat. For cooking and spreads, use olive oil, butter, or coconut oil instead of margarine or shortening.

Go Long,

Wiley