Fats are important in foods as well as in the body. Many of the compounds that give foods their flavors and aromas are found in fats and oils. The delicious aromas associated with bacon, ham, and other meats, as well as with onions being sautéed, come from fats. Fats also influence the texture of many foods, enhancing smoothness, creaminess, moistness, or crispness. In addition, four vitamins—A, D, E, and K—are soluble in fat. When the fat is removed from a food, many fat-soluble compounds, including these vitamins, are also removed.
Fats are also an important part of most people’s ethnic or national cuisines. Each culture has its own favorite food sources of fats and oils. In Canada, canola oil (also known as rapeseed oil) is widely used. In the Mediterranean area, Greeks, Italians, and Spaniards rely heavily on olive oil. Both canola oil and olive oil are rich sources of monounsaturated fatty acids. Asians use the polyunsaturated oil of soybeans. Jewish people traditionally employ chicken fat. Everywhere in North America, butter and margarine are widely used.
Finding the Fats in Foods
To choose fats wisely, you need to know which foods offer unsaturated oils that provide the essential fatty acids and which foods are loaded with solid fats—the saturated and trans fats. Also important for many people is learning to control portion sizes, particularly portions of fatty foods that can pack hundreds of calories into just a few bites.
Keep in mind that, whether solid or liquid, essential or nonessential, all fats bring the same abundant calories to the diet, and excesses contribute to body fat stores. According to the Dietary Guidelines for Americans, no benefits can be expected when oil is added to an already fat-rich eating pattern. The following amounts of these fats contain about 5 grams of pure fat, providing 45 calories and negligible protein and carbohydrate:
- 1 teaspoon of oil or shortening
- 11⁄2 teaspoons of mayonnaise, butter, or margarine
- 1 tablespoon of regular salad dressing, cream cheese, or heavy cream
- 11⁄2 tablespoons of sour cream
The solid fat of some foods, such as the rim of fat on a steak, is visible (and therefore identifiable and removable). Other solid fats, such as those in candy, cheeses, coconut, hamburger, homogenized milk, and lunch meats, are invisible (and therefore easily missed or ignored). Equally hidden are the solid fats blended into biscuits, cakes, cookies, chip dips, ice cream, mixed dishes, pastries, sauces, and creamy soups, and integral to fried foods. Invisible fats supply the majority of solid fats in the U.S. diet.
Milk and Milk Products
Milk products go by different names that reflect their varying fat contents. A cup of homogenized whole milk contains the protein and carbohydrates of fat-free milk, but in addition, it contains about 80 extra calories from butterfat, a solid fat. A cup of reduced-fat (2 percent fat) milk falls be- tween whole milk and fat-free, with 45 calories from fat. Note that cream and butter do not appear in the milk and milk products group.
Milk and yogurt are rich in calcium and protein, but cream and butter are not. Cream and butter are solid fats, as are whipped cream, sour cream, and cream cheese. Other cheeses, grouped with milk products, vary in their fat contents and are major contributors to saturated fat in people’s diets.
Meats conceal a good deal of the fat—and much of the solid fat— that people consume. To help “see” the fat in meats, it is useful to think of them in three categories according to their fat contents: lean, medium-fat, and high-fat meats. Meats in all three categories contain about equal amounts of protein, but their fat, saturated fat, and kcalorie amounts vary significantly.
The USDA Food Patterns suggest that most adults limit their intake of protein foods to about 5 to 7 ounces per day. For comparison, the smallest fast-food hamburger weighs about 3 ounces. A steak served in a restaurant often runs 8, 12, or 16 ounces, more than a whole day’s meat allowance. You may have to weigh a serving or two of meat to see how much you are eating.
People think of meat as a protein food, but calculation of its nutrient content reveals a surprising fact. A big (4-ounce) fast-food hamburger sandwich contains 24 grams of protein and 18 grams of fat, 7 of them saturated fat. Because protein offers 4 calories per gram and fat offers 9, the sandwich provides 96 calories from protein but 162 calories from fat. Hot dogs, fried chicken sandwiches, and fried fish sandwiches also provide hundreds of fat calories, mostly from invisible solid fat. Because so much meat fat is hidden from view, meat eaters can easily and unknowingly consume a great many grams of solid fat from this source.
When choosing beef or pork, look for lean cuts named loin or round from which the fat can be trimmed, and eat small portions. Chicken and turkey flesh are naturally lean, but commercial processing and frying add solid fats, especially in “patties,” “nuggets,” “fingers,” and “wings.”
Chicken wings are mostly skin, and a chicken stores most of its fat just under its skin. The tastiest wing snacks have also been fried in cooking fat (often a hydrogenated, saturated type with trans-fatty acids); smothered with a buttery, spicy sauce; and then dipped in blue cheese dressing, making wings an extraordinarily high-fat snack. People who snack on wings may want to plan on eating low-fat foods at several other meals to balance them out.
Vegetables, Fruits, and Grains
Choosing vegetables, fruits, whole grains, and legumes helps lower the saturated fat, cholesterol, and total fat content of the diet. Most vegetables and fruits naturally contain little or no fat; avocados and olives are exceptions, but most of their fat is unsaturated, which is not harmful to heart health.
Most grains contain only small amounts of fat. Some refined grain products such as fried taco shells, croissants, and biscuits are high in saturated fat, so consumers need to read food labels. Similarly, many people add butter, margarine, or cheese sauce to grains and vegetables, which raises their saturated and trans fat contents. Because fruits are often eaten without added fat, a diet that includes several servings of fruit daily can help a person meet the dietary recommendations for fat.
A diet rich in vegetables, fruits, whole grains, and legumes offers abundant vitamin C, folate, vitamin A, vitamin E, and dietary fiber—all important in supporting health. Consequently, such a diet protects against disease both by reducing saturated fat, cholesterol, and total fat and by increasing nutrients. It also provides valuable phytochemicals that help defend against heart disease.
Cutting Solid Fats and Choosing Unsaturated Fats
Meeting today’s lipid guidelines can be challenging. Reducing intakes of saturated and trans-fatty acids, for example, involves identifying food sources of these fatty acids—that is, foods that contain solid fats. Then, replacing them appropriately involves identifying unsaturated oils. To help simplify these tasks, the Dietary Guidelines suggest:
- Selecting the most nutrient-dense foods from all food groups. Solid fats and high- kcalorie choices can be found in every food group.
- Consuming fewer and smaller portions of foods and beverages that contain solid fats.
- Replacing solid fats with liquid oils whenever possible.
- Checking Nutrition Facts labels and selecting foods with little saturated fat and no trans fat.
Such advice is easily dispensed but not easily followed. The first step in doing so is learning which foods contain heavy doses of solid fats.
The best diet for heart health is also rich in fruits, vegetables, nuts, and whole grains that offer many health advantages by supplying abundant nutrients, fiber, and phytochemicals.
Fats and Calories
Removing fat from food also removes energy. A pork chop with the fat trimmed to within a half-inch of the lean provides 290 calories; with the fat trimmed off completely, it supplies 174 calories. A baked potato with butter and sour cream (1 tablespoon each) has 315 calories; a plain baked potato has 188 calories. The single most effective step you can take to reduce the energy value of a food is to eat it with less fat.
Choosing Unsaturated Fats
When a person does eat fats, those to choose are the unsaturated ones. Remember, the softer a fat is, the more unsaturated it is. Generally speaking, vegetable and fish oils are rich in polyunsaturates, olive oil and canola oil are rich in monounsaturates, and the harder fats—animal fats—are more saturated. Remember, however, that vegetable fat or vegetable oil doesn’t always mean unsaturated fat. Both coconut oil and palm oil, for example, which are often used in nondairy creamers, are saturated fats, and both raise blood cholesterol.
Don’t Overdo Fat Restriction
Some people actually manage to eat too little fat— to their detriment. Among them are young women and men with eating disorders. As a practical guideline, it is wise to include the equivalent of at least a teaspoon of fat in every meal.
Today, consumers can choose from thousands of fat-reduced products. Many bakery goods, lunch meats, cheeses, spreads, frozen desserts, and other products made with fat replacers offer less than half a gram of fat, saturated fat, and trans fat in a serving. Some of these products contain artificial fats, and others use conventional ingredients in unconventional ways to reduce fats and calories. Among the latter, manufacturers can:
- Add water or whip air into foods.
- Add fat-free milk to creamy foods.
- Use lean meats and soy protein to replace high-fat meats.
- Bake foods instead of frying them.
Common food ingredients such as fibers, sugars, or proteins can also take the place of fats in some foods. Products made from sugars or proteins still provide calories but far fewer calories from fats. Manufactured fat replacers consist of chemical derivatives of carbohydrate, protein, or fat, or modified versions of foods rich in those constituents.
A familiar example of artificial fat that has been approved for use in snack foods such as potato chips, crackers, and tortilla chips is olestra. Olestra’s chemical structure is similar to that of a regular fat (a triglyceride) but with important differences. A triglyceride is composed of a glycerol molecule with three fatty acids attached, whereas olestra is made of a sucrose molecule with six to eight fatty acids attached. Enzymes in the digestive tract cannot break the bonds of olestra, so unlike sucrose or fatty acids, olestra passes through the system unabsorbed.
The FDA’s evaluation of olestra’s safety addressed two questions. First, is olestra toxic? Research on both animals and humans supports the safety of olestra as a partial replacement for dietary fats and oils, with no reports of cancer or birth defects. Second, does olestra affect either nutrient absorption or the health of the digestive tract?
When olestra passes through the digestive tract unabsorbed, it binds with the fat-soluble vitamins A, D, E, and K and carries them out of the body, robbing the person of these valuable nutrients. To compensate for these losses, the FDA requires the manufacturer to fortify olestra with vitamins A, D, E, and K. Saturating olestra with these vitamins does not make the product a good source of vitamins, but it does block olestra’s ability to bind with the vitamins from other foods. An asterisk in the ingredients list informs consumers that these added vitamins are “dietarily insignificant.”
Consumers need to keep in mind that low-fat and fat-free foods still deliver calories. Decades ago, consumers hailed the arrival of artificial sweeteners as a weight-loss wonder, but in reality, calories saved by using artificial sweeteners were readily replaced by calories from other foods. Alternatives to fat can help to lower energy intake and support weight loss only when they actually replace fat and energy in the diet.
Read Food Labels
Labels list total fat, saturated fat, trans fat, and cholesterol contents of foods. Because each package provides information for a single serving, and serving sizes are standardized, consumers can easily compare similar products.
Fats in foods contribute to sensory appeal—enhancing the flavor, aroma, and texture of foods.
Fats in foods deliver fat-soluble vitamins, energy, and essential fatty acids.
While some fat in the diet is necessary, the Dietary Guidelines for Americans recommend limiting intakes of saturated fat and trans fat.
Fats added to foods during preparation or at the table are a major source of fat in the diet.
The choice between whole and fat-free milk products can make a big difference to the fat, saturated fat, and cholesterol content of a diet.
Meats account for a large proportion of hidden solid fats in many people’s diets.
Most people consume more meat than is recommended.
Most vegetables and fruits naturally contain little or no fat.
Grain products such as croissants and biscuits can be high in saturated fat, so consumers need to read food labels to learn which foods in this group contain fats.
Consumers today can choose from an array of fat-reduced products, and many bakery goods and other foods made with fat replacers offer less than half a gram of fat, saturated fat, and trans fat in a serving.
Some products use artificial fats such as olestra, while others use conventional ingredients such as water or fat-free milk to reduce fat and calories.
Food labels list total fat, saturated fat, cholesterol, and trans fat.