Trans Fatty Acids
You've probably heard it by now: avoid trans fatty acids--those in fried foods, margarine, and the "hydrogenated" or "partially hydrogenated" ingredient you see on the label of that tempting package of cookies or donuts. But what's all the fuss?
"The problem with trans fatty acids is that your body doesn't know what to do with them," says Brian Olshansky, MD, University of Iowa Health Care professor of internal medicine who treats patients with heart conditions.
"Trans fatty acids may help preserve food so that it tastes good, but your body can't break them down and use them correctly," Olshansky says. "Normal fats are very supple and pliable, but the trans fatty acid is a stiff fat that can build up in the body and create havoc."
The areas affected include the lining of your blood vessels and brain surfaces, where the build-up can cause dysfunction. Trans fatty acids are linked to obesity, heart disease, diabetes, high cholesterol and even sudden cardiac death.
If that's not enough to give you pause next time you double your order of fries or take a bite of artificial cheese pizza, consider that the chemical recipe for a trans fatty acid involves putting hydrogen atoms (thus that "hydrogenated" term you see) in the "wrong place," Olshansky says. "It's like making a plastic."
And who would want to eat plastic?
Olshansky acknowledges that it is hard to avoid trans fatty acids in the typical American diet. You often see "partially hydrogenated" in ingredient labels of processed foods, and the higher up those words appear on the list, the more trans fatty acids contained in the product. Fast foods and cheaper foods tend to include these fats because they stabilize the ingredients. "I'm recommending to my patients not to eat products with trans fatty acids and to keep away from processed foods and fast foods until they improve," Olshansky says.
Go for what's fresh instead, he said, citing a study published in the Journal of the American Medical Association that showed eating fresh food can lower your cholesterol as much as taking a statin medication.
Variety also is key to making positive changes in what you eat, says Denise Schiller, clinical dietician with the Cardiovascular Health Assessment, Management and Prevention Service (CHAMPS) of UI Heart and Vascular Center.
"Most people don't have much variety in their diet," Schiller says. "I hone in on helping people watch their portion sizes, eat foods that have a lower fat content and use beneficial fats."
"Good" fats, used in moderation, are monounsaturated and polyunsatured fats. Monounsatured fats include olive, canola, and peanut oils and are best used for cooking or baking. Schiller also reminds people to store these fats in a cabinet away from light to keep them from getting rancid. Polyunsaturated fats include soybean, corn and sunflower oils and are ideal for salad dressings and other cold uses. Likewise, these oils should be stored in the refrigerator. You can also supplement your diet with omega-3 fatty acids found in fish, nuts and some grains. Omega-3 fats are good fats that reduce the risk of heart disease and can provide a mental boost.
New labeling for foods is expected in 2006, and total trans fats will then be listed. However, not all trans fatty acids, or trans fats, are the same. Some are good, and the labeling will not distinguish between the good and bad trans fats. One good trans fat called CLA (conjugated linolenic acid) actually improves the immune system, reduces the risk of cancer and may be added to milk on purpose, Olshansky says.
Schiller and Olshansky both recommend avoiding margarine with partially hydrogenated oils. Instead, try the newer margarines that are light or made with yogurt and do not contain trans fats.
Avoiding foods with trans fatty acids means giving up some comfort foods--and that might make you feel less satisfied with a meal. However, whole grains can make you feel full. That means choosing breads with the label "100 percent whole-wheat," not just "wheat."
"Whole-wheat bread provides more nutrition and fiber and makes you feel fuller," Schiller says. "Soluble fiber, in particular, can help reduce cholesterol and have many other benefits."
Before making any changes to your diet or health routine, it always is best to consult with your physician or other health care professional.
University of Iowa Health Science Relations and
Brian Olshansky, MD
Professor of Internal Medicine
First Published: 2003
Last Revised: October 2003
Peer Review Status: Internally Peer Reviewed