The Dangers of Hidden Fats in Foods

How to Reduce Consumption of Trans Fats

Jun 15, 2009 Jacqueline Trovato

Fat is a major source of energy and aids the body in absorbing vitamins. It's important for proper growth, development and keeping us healthy.

But there are fats to avoid, such as saturated fats found in butter, solid shortening, and lard, and trans fats, found in vegetable shortenings, some margarines, crackers, cookies, snack foods and other foods made with or fried in partially hydrogenated oils.

Not All Fats Are the Same

When it comes to fat, trans fat is considered by some doctors to be the worst of them all because of its doubly bad impact on cholesterol levels. Unlike other fats, trans fat raises your "bad" (LDL) cholesterol and lowers your "good" (HDL) cholesterol.

Low-density lipoprotein (LDL) LDL, or "bad," cholesterol transports cholesterol throughout your body. LDL cholesterol, when elevated, builds up in the walls of your arteries, making them hard and narrow.

High-density lipoprotein (HDL). HDL, or "good," cholesterol picks up excess cholesterol and takes it back to your liver.

A high LDL cholesterol level in combination with a low HDL cholesterol level increases the risk of heart disease, and is the leading killer of men and women.

How Trans Fats Are Formed

Unlike other fats, the majority of trans fat is formed when liquid oils are made into solid fats like shortening and hard margarine. However, a small amount of trans fat is found naturally, primarily in some animal-based foods. Essentially, trans fat is made when hydrogen is added to vegetable oil -- a process called hydrogenation. Hydrogenation increases the shelf life and flavor stability of foods containing these fats. Unsaturated fats, such as monounsaturated and polyunsaturated, do not raise LDL cholesterol and are beneficial when consumed in moderation.

Other Risks Related to the Consumption of Trans Fats

Trans fat has also been shown to have some other harmful effects:

Increases triglycerides. Triglycerides are a type of fat found in the blood. A high triglyceride level may contribute to hardening of the arteries (atherosclerosis) or thickening of the artery walls — which increases the risk of stroke, diabetes, heart attack and heart disease.

Increases Lp(a) lipoprotein. Lp(a) is a type of LDL cholesterol found in varying levels in the blood, depending upon a person’s genetic makeup. High levels of Lp(a) — independent of other cholesterol levels — increases the risk of heart disease.

Causes more inflammation. Trans fat may increase inflammation, a process where the body responds to injury. It's thought that inflammation plays a key role in the formation of fatty blockages in heart blood vessels. Trans fat damages the cells lining blood vessels, leading to inflammation.

How to Avoid Trans Fats

To avoid trans fats, read the Nutrition Facts panel on food labels, and choose the food with the lower amounts of saturated fat, trans fat, and cholesterol. It is recommended that consumers keep their intake of these nutrients as low as possible while consuming a nutritionally adequate diet.

Read food labels carefully. Look for the words "partially hydrogenated" vegetable oil. That's another term for trans fat. The word "shortening" also is a clue: Shortening contains some trans fat. “Fully" or "completely" hydrogenated oil doesn't contain trans fat. However, if the label says just "hydrogenated" vegetable oil, it could mean the oil contains some trans fat.

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, use the Quick Guide to %DV: 5%Daily Value (DV) or less is low and 20%DV or more is high. (There is no %DV for trans fat.)

If trans fat is not declared on the label, contact the manufacturer listed on the label.

The American Heart Association recommends that no more than 1 percent of a person’s total daily calories be trans fat. If someone consumes 2,000 calories a day, that works out to 2 grams of trans fat or less, or about 20 calories.

Restaurant Food and Trans Fats

The good news is trans fat is showing up less in food, especially food on grocery store shelves. But for those who eat out a lot, they should be aware that some restaurants continue to use trans fat. Trans fat is typically a part of the oil restaurants use to fry food. A large serving of french fries at some restaurants can contain 5 grams or more of trans fat.

Some restaurants put nutritional information on their menus, but most aren't required to list trans fat content. Some cities, such as New York City, have banned restaurants from using trans fat.

A Few More Tips

Here are some tips to use to keep consumption of saturated fat, trans fat, and cholesterol low while consuming a nutritionally adequate diet.

• Choose Alternative Fats. Replace saturated and trans fats in the diet with mono- and polyunsaturated fats. These fats do not raise LDL (or "bad") cholesterol levels and have health benefits when eaten in moderation. Some 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 that are being studied to determine if they offer protection against heart disease.
• Choose Lean Meats, such as poultry (without skin, not fried), lean beef and pork (trim visible fat, not fried).
• Ask Before Ordering When Eating Out. A good tip to remember is to ask which fats are being used in the preparation of foods when eating or ordering out.
• Watch Calories. 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.

For more information visit the American Heart Association’s Website.

The copyright of the article The Dangers of Hidden Fats in Foods in Nutrition is owned by Jacqueline Trovato. Permission to republish The Dangers of Hidden Fats in Foods in print or online must be granted by the author in writing.

nutrition/trans fat