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Revealing Trans Fats

Scientific evidence shows that consumption of saturated fat, trans fat, and dietary cholesterol raises low-density lipoprotein (LDL), or "bad" cholesterol levels, which increases the risk of coronary heart disease (CHD).

According to the National Heart, Lung, and Blood Institute of the National Institutes of Health, more than 12.5 million Americans have coronary heart disease (CHD), and more than 500,000 die each year. That makes CHD one of the leading causes of death in the United States.

The Food and Drug Administration has required that saturated fat and dietary cholesterol be listed on food labels since 1993. Starting Jan. 1, 2006, listing of trans fat will be required as well. With trans fat added to the Nutrition Facts label, you will know for the first time how much of all three--saturated fat, trans fat, and cholesterol--are in the foods you choose. Identifying saturated fat, trans fat, and cholesterol on the food label gives you information you need to make food choices that help reduce the risk of CHD. This revised label will be of particular interest to people concerned about high blood cholesterol and heart disease.

However, everyone should be aware of the risk posed by consuming too much saturated fat, trans fat, and cholesterol. But what is trans fat, and how can you limit the amount of this fat in your diet?

What is Trans Fat?

Basically, trans fat is made when manufacturers add hydrogen to vegetable oil--a process called hydrogenation. Hydrogenation increases the shelf life and flavor stability of foods containing these fats.

Trans fat can be found in vegetable shortenings, some margarines, crackers, cookies, snack foods, and other foods made with or fried in partially hydrogenated oils. Unlike other fats, the majority of trans fat is formed when food manufacturers turn liquid oils into solid fats like shortening and hard margarine. A small amount of trans fat is found naturally, primarily in dairy products, some meat, and other animal-based foods.

Trans fat, like saturated fat and dietary cholesterol, raises the LDL cholesterol that increases your risk for CHD. Americans consume on average 4 to 5 times as much saturated fat as trans fat in their diets. Although saturated fat is the main dietary culprit that raises LDL, trans fat and dietary cholesterol also contribute significantly.

Are All Fats the Same?

Simply put: No. Fat is a major source of energy for the body and aids in the absorption of vitamins A, D, E, and K and carotenoids. Both animal- and plant-derived food products contain fat, and when eaten in moderation, fat is important for proper growth, development, and maintenance of good health. As a food ingredient, fat provides taste, consistency, and stability and helps you feel full. In addition, parents should be aware that fats are an especially important source of calories and nutrients for infants and toddlers (up to 2 years of age), who have the highest energy needs per unit of body weight of any age group.

While unsaturated fats (monounsaturated and polyunsaturated) are beneficial when consumed in moderation, saturated and trans fats are not. Saturated fat and trans fat raise LDL cholesterol levels in the blood. Dietary cholesterol also contributes to heart disease. Therefore, it is advisable to choose foods low in saturated fat, trans fat, and cholesterol as part of a healthful diet.

What Can You Do About Saturated Fat, Trans Fat, and Cholesterol?

When comparing foods, look at the Nutrition Facts panel, and choose the food with the lower amounts of saturated fat, trans fat, and cholesterol. Health experts recommend that you keep your intake of saturated fat, trans fat, and cholesterol as low as possible while consuming a nutritionally adequate diet. However, these experts recognize that eliminating these three components entirely from your diet is not practical because they are unavoidable in ordinary diets.

Where Can You Find Trans Fat on the Food Label?

Although some food products already have trans fat on the label, food manufacturers had until January 2006 to list it on all their products. You will find trans fat listed on the Nutrition Facts panel directly under the line for saturated fat.

How Do Your Choices Stack Up?

With the addition of trans fat to the Nutrition Facts panel, you can review your food choices and see how they stack up.

The following table illustrates total fat, saturated fat, trans fat, and cholesterol content per serving for selected food products.

Total Fat, Saturated Fat, Trans Fat, and Cholesterol Content Per Serving*

*Nutrient values rounded based on FDA's nutrition labeling regulations. ** Butter values from FDA Table of Trans Values, 1/30/95. ? Values derived from 2002 USDA National Nutrient Database for Standard Reference, Release 15. ?? Prerelease values derived from 2003 USDA National Nutrient Database for Standard Reference, Release 16. ? 1995 USDA Composition Data.

Don't assume similar products are the same. Be sure to check the Nutrition Facts panel because even similar foods can vary in calories, ingredients, nutrients, and the size and number of servings in a package. Even if you continue to buy the same brand of a product, check the Nutrition Facts panel frequently because ingredients can change at any time.

How Can You Use the Label to Make Heart-Healthy Food Choices?

The Nutrition Facts panel can help you choose foods lower in saturated fat, trans fat, and cholesterol. Compare similar foods and choose the food with the lower combined saturated and trans fats and the lower amount of cholesterol.

Although the updated Nutrition Facts panel will list the amount of trans fat in a product, it will not show a Percent Daily Value (%DV). While scientific reports have confirmed the relationship between trans fat and an increased risk of CHD, none has provided a reference value for trans fat or any other information that the FDA believes is sufficient to establish a Daily Reference Value or a %DV.

There is, however, a %DV shown for saturated fat and cholesterol. To choose foods low in saturated fat and cholesterol, use the general rule of thumb that 5 percent of the Daily Value or less is low and 20 percent or more is high.

You can also use the %DV to make dietary trade-offs with other foods throughout the day. You don't have to give up a favorite food to eat a healthy diet. When a food you like is high in saturated fat or cholesterol, balance it with foods that are low in saturated fat and cholesterol at other times of the day.

Do Dietary Supplements Contain Trans Fat?

Would it surprise you to know that some dietary supplements contain trans fat from partially hydrogenated vegetable oil as well as saturated fat or cholesterol? It's true. As a result of the FDA's new label requirement, if a dietary supplement contains a reportable amount of trans or saturated fat, which is 0.5 gram or more, dietary supplement manufacturers must list the amounts on the Supplement Facts panel. Some dietary supplements that may contain saturated fat, trans fat, and cholesterol include energy and nutrition bars.

Fat Tips

Here are some practical tips you can use every day to keep your consumption of saturated fat, trans fat, and cholesterol low while consuming a nutritionally adequate diet.

• Check the Nutrition Facts panel to compare foods because the serving sizes are generally consistent in similar types of foods. Choose foods lower in saturated fat, trans fat, and cholesterol. For saturated fat and cholesterol, keep in mind that 5 percent of the daily value (%DV) or less is low and 20 percent or more is high. (There is no %DV for trans fat.)
• Choose alternative fats. Replace saturated and trans fats in your diet with monounsaturated and polyunsaturated fats. These fats do not raise LDL cholesterol levels and have health benefits when eaten in moderation. Sources of monounsaturated fats include olive and canola oils.
• Sources of polyunsaturated fats include soybean oil, corn oil, sunflower oil and foods like nuts and fish.
• Choose vegetable oils (except coconut and palm kernel oils) and soft margarines (liquid, tub, or spray) more often because the amounts of saturated fat, trans fat, and cholesterol are lower than the amounts in solid shortenings, hard margarines, and animal fats, including butter.
• Consider fish. Most fish are lower in saturated fat than meat. Some fish, such as mackerel, sardines, and salmon, contain omega-3 fatty acids, which are being studied to determine if they offer protection against heart disease.
• Choose lean meats, such as poultry without the skin and not fried and lean beef and pork, not fried, with visible fat trimmed.
• Ask before you order when eating out. A good tip to remember is to ask which fats are being used in the preparation of your food when eating or ordering out.
• Watch calories. Don't be fooled! Fats are high in calories. All sources of fat contain 9 calories per gram, making fat the most concentrated source of calories. By comparison, carbohydrates and protein have only 4 calories per gram. To keep your intake of saturated fat, trans fat, and cholesterol low:
• Look at the Nutrition Facts panel when comparing products. Choose foods low in the combined amount of saturated fat and trans fat and low in cholesterol as part of a nutritionally adequate diet.
• Substitute alternative fats that are higher in mono- and polyunsaturated fats like olive oil, canola oil, soybean oil, corn oil, and sunflower oil.

Highlights of the Final Rule on Trans Fat

• Manufacturers of conventional foods and some dietary supplements will be required to list trans fat on a separate line, immediately under saturated fat on the nutrition label.
• Food manufacturers have until Jan. 1, 2006, to list trans fat on the nutrition label. The phase-in period minimizes the need for multiple labeling changes, allows small businesses to use current label inventories, and provides economic savings.
• FDA's regulatory chemical definition for trans fatty acids is all unsaturated fatty acids that contain one or more isolated (i.e., nonconjugated) double bonds in a trans configuration. Under the agency's definition, conjugated linoleic acid would be excluded from the definition of trans fat.
• Dietary supplement manufacturers must also list trans fat on the Supplement Facts panel when their products contain reportable amounts (0.5 gram or more) of trans fat. Examples of dietary supplements with trans fat are energy and nutrition bars.

For More Information

Questions and Answers on the Trans Fat Final Rule www.cfsan.fda.gov/~dms/qatrans2.html

Backgrounder www.fda.gov/oc/initiatives/transfat/backgrounder.html

Guidance on How to Understand and Use the Nutrition Facts Panel on Food Labels www.cfsan.fda.gov/~dms/foodlab.html

Quiz -- Test Your Food Label Knowledge www.cfsan.fda.gov/~dms/flquiz1.html

Federal Register Final Rule: Trans Fatty Acids in Nutrition Labeling, Nutrient Content Claims, and Health Claims www.cfsan.fda.gov/~lrd/fr03711a.html

Advance Notice of Proposed Rulemaking to solicit information on trans fat nutrient and health claims www.cfsan.fda.gov/~lrd/fr03711b.html

"What's New on the Nutrition Facts Label? Trans Fat Now Listed with Saturated Fat and Cholesterol." www.cfsan.fda.gov/~dms/lab-cat.html#transfat

Major Food Sources of Trans Fat for American Adults
(Average Daily Trans Fat Intake is 5.8 Grams or 2.6 Percent of Calories)

Data based on FDA's economic analysis for the final trans fatty acid labeling rule, "Trans Fatty Acids in Nutrition Labeling, Nutrient Content Claims, and Health Clains" (July 11, 2003)

Source: FDA Consumer magazine September-October 2003 Issue Pub No. FDA04-1329C (This article originally appeared in the September-October 2003 FDA Consumer and contains revisions made in September 2003 and May 2004.)
Adapted by Editorial Staff, September 2006
Last update, August 2008