High-fat diets are associated with an increased incidence of obesity, heart disease, hypertension, cancer, diabetes and gallbladder disease. So government agencies and health professionals recommend reduced intake of total fat (30% or less of total calories) and saturated fat (10% or less of total calories).
The percentage of calories as fat dropped from 42% in 1965 to 34% in 1994. But, this downward trend is misleading. Total calorie intake has increased by about 300 cals. daily, so the percentage (not the amount) of calories from fat has declined. At the same time, the prevalence of obesity rose to about 30% of American adults and 20% of children.
Lowfat foods: Until recently, the only practical advice was to reduce or eliminate high-fat foods or use the limited (and not always palatable) lowfat options available. But, the food industry has created over 5,600 lowfat foods.
Advances in food technology and the Food and Drug Admin.'s (FDA) recent approval of "Olean" have greatly increased consumer options for fat-modified foods. A 1996 survey revealed 88% of Americans eat lowfat, reduced fat, or fat-free foods.
The current trend is to reformulate fat-free foods into lowfat foods that taste good. Fat contributes to the sensory and functional properties of food including texture and flavor.
Fat replacers: According to American Dietetic Assn. (ADA) spokesperson Cindy Moore, MS, RD (Cleveland, OH), "There are three types of fat replacers—carbohydrate-based, protein-based and fat-based."
Moore says: "Most fat replacers are carbohydrate-based. These ingredients include cellulose, gums, dextrins, fiber, starches, maltodextrins and polydextrose. In addition, pureed prunes and applesauce are sometimes used in baked goods. A new fat replacer, NuTrim, is made from the soluble fiber in oats and helps lower high blood levels of LDL-cholesterol and risk for heart disease.
"These fat replacers provide thickness and bulk but only 1 to 4 calories per gram; fat adds 9 calories per gram. They can't be used in fried foods. Instead, they are used in processed meats, frozen desserts, baked goods, dairy products, salad dressings, sour cream, gravy, sauces, soups and confections."
Protein-based: "Protein-based fat replacers are usually made from egg white or skim milk, e.g., Simplesse, Veri-lo, Dairy-lo," Moore explains. "They stabilize fat emulsions and add creaminess to cheeses, mayonnaise, butter, sour cream, bakery products, sauces, frozen dairy desserts and salad dressings.
"Protein-based fat replacers contribute only 1 to 4 calories per gram. Most can't be heated to high temperatures (as in baked goods), because the protein coagulates and loses its creamy texture."
Fat-based: ADA spokesperson Sheah Rarback, MS, RD, in Miami, FL, says: "Some fat replacers are made from chemically-altered fats. These include Salatrim (Benefat) and Olestra (Olean). Salatrim contributes only 5 calories per gram since it is partially absorbed by the gut. Salatrim doesn't have any adverse effect on absorption of fat-soluble vitamins (A, D, E and K) or blood lipids (e.g., cholesterol). It is used in confections, spreads, baked goods, chocolate, dairy foods and snacks."
About Olestra: "Olestra is made from vegetable oils and sugar (sucrose polyester). It is calorie-free, since it is bulky and can't be digested. Olestra is also heat-stable," Rarback points out.
"Since fat-soluble vitamins can't be fully absorbed, the manufacturer adds these vitamins to foods containing Olestra, e.g. savory snacks like potato chips. But, other disease-fighting carotenoids are not added back."
Rarback says: "Olestra may cause gastrointestinal distress like cramps and diarrhea in some people. But, when eaten in moderation, olestra does not cause these problems."
Are they safe: Says Moore: "The manufacturer of Olestra submitted over 100 studies to FDA confirming its safety. Safety studies are ongoing.
"The majority of fat replacers contain ingredients that are on the FDA's GRAS (generally recognized as safe) list based on scientific information and long history of use. These include carbohydrate polymers, gums, gels, starches, whey proteins and fat emulsifiers."
The advantages: In a position statement (April 1998), the ADA affirmed that "fat replacers may offer a safe, feasible and effective means to maintain the palatability of diets with controlled amounts of fat and/or energy (calories)."
ADA spokesperson Bettye Nowlin, MPH, RD (Los Angeles, CA) agrees. "People who choose reduced fat and fat-free foods should still eat a diet consistent with the Dietary Guidelines. Moderation, variety and balance are essential in following the USDA Food Guide Pyramid including five food groups: Milk, Meat, Fruits, Vegetables and Grains. Foods made with fat replacers can be incorporated into a healthy diet," she contends.
"In the future," she says, "consumers can expect to see more good-tasting lowfat and fat-free foods. Cost and convenience will also determine acceptance."
Weight loss: "Fat replacers can be an effective tool for weight control," Rarback says, "but they're not the answer to the obesity epidemic in the U.S. Certainly lowfat and fat-free foods can help reduce calorie and fat intake in our diets. So these foods may help lower blood cholesterol and risk of chronic diseases.
"But, weight loss depends on total calories eaten and expended daily through exercise. Lowfat and fat-free foods are not a magic bullet for losing weight."
Rarback points out: "Some people may overcompensate for eating lowfat foods (with a low satiety value) by eating more of them. Then, little or no weight loss occurs."
Moore agrees. "People mistakenly think they can eat unlimited amounts of lowfat and fat-free foods and still lose weight. But, these foods are not calorie-free. They may contain the same or more calories than the full-fat foods they replace. Many are high in sugar content which may be a problem for people with diabetes or high triglycerides.