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Sources

Fat replacers may be carbohydrate-, protein- or fat-based substances.

The first to hit the market used carbohydrate as the main ingredient. Avicel, for example, is a cellulose gel introduced in the mid-1960s as a food stabilizer. Carrageenan, a seaweed derivative, was approved for use as an emulsifier, stabilizer and thickener in food in 1961. Its use as a fat replacer became popular in the early 1990s. Litesse (polydextrose) came on the market in 1981 as a humectant, which helps retain moisture. Others in this category include dextrins, maltodextrins, fiber, gums, starch, and modified food starch. FDA has affirmed many carbohydrate-based fat replacers as GRAS.

Although their original intent was to perform certain technical functions in food that would improve overall quality, some carbohydrate-based fat replacers are now used specifically to reduce a food's calorie content. They provide from zero to 4 calories per gram. They are used in a variety of foods, including dairy-type products, sauces, frozen desserts, salad dressings, processed meats, baked goods, spreads, chewing gum, and sweets.

Protein-based fat substitutes came along in the early 1990s. These and fat-based replacers were designed specifically to replace fat in foods.

One form, Microparticulated Protein Product (MPP), such as Simplesse and Trailblazer, is made from whey protein or milk and egg protein. These fat replacers provide 1 to 4 calories per gram, depending on their water content, and are approved for use in frozen dessert-type foods. FDA has agreed that whey-based MPP conforms to FDA's definition of whey protein concentrate, such as the fat replacer Dairy-Lo, a GRAS substance. Therefore, whey-based MPP can be used in other foods, including reduced-fat versions of butter, sour cream, cheese, yogurt, salad dressing, margarine, mayonnaise, baked goods, coffee creamer, soups, and sauces.

Another type of protein-based fat replacers, called protein blends, combine animal or vegetable protein, gums, food starch, and water. They are made with FDA-approved ingredients and are used in frozen desserts and baked goods.

Olestra

Olestra is an example of a fat-based fat replacer. FDA approved olestra (brand name Olean), made by Procter & Gamble Co. of Cincinnati, in January 1996, for use in preparing potato chips, crackers, tortilla chips, and other savory snacks. Procter & Gamble said it expected to begin test-marketing olestra-containing products in 1996.

Olestra has properties similar to those of naturally occurring fat, but it provides zero calories and no fat. That's because olestra is undigestible. It passes through the digestive tract but is not absorbed into the body. This is due to its unique configuration: a center unit of sucrose (sugar) with six, seven or eight fatty acids attached.

Olestra's configuration also makes it possible for the substance to be exposed to high temperatures, such as frying — a quality most other fat replacers lack.

As promising as olestra sounds, it does have some drawbacks. Studies show that it may cause intestinal cramps and loose stools in some individuals.

Also, according to clinical tests, olestra reduces the absorption of fat-soluble nutrients, such as vitamins A, D, E, and K and carotenoids, from foods eaten at the same time as olestra-containing products. Tests by Procter & Gamble show that no reduction in absorption of fat-soluble vitamins will occur when proper levels of vitamins are added for compensation to olestra-containing foods.

To address these concerns, FDA approved olestra on conditions that vitamins A, D, E, and K be added to olestra-containing foods and that Procter & Gamble continue studies on consumption and long-term effects of olestra. These studies will be reviewed at an FDA Food Advisory Committee meeting in mid-1998.

To provide consumers with information about olestra's possible effects, FDA also required that the following interim labeling statement appear on products made with olestra:

"This Product contains Olestra. Olestra may cause abdominal cramping and loose stools. Olestra inhibits the absorption of some vitamins and other nutrients. Vitamins A, D, E and K have been added."

FDA has invited public comment on the need for such a label statement and on the statement's adequacy and clarity. The agency will evaluate those comments before issuing a final label statement.

Concern with olestra's drawbacks led one of olestra's critics, the Center for Science in the Public Interest — a nonprofit consumer advocacy organization — to file an objection to FDA's approval. FDA's response to the objection is pending.

Other Replacers

Some other fat-based replacers are being considered or developed: Salatrim (which stands for short and long-chain acid triglyceride molecules) is the generic name for a family of reduced-calorie fats that are only partially absorbed in the body. Salatrim provides 5 calories per gram. A petition seeking FDA's affirmation that Salatrim is GRAS was filed in June 1994. An example of its use is in Hershey Co.'s reduced-fat baking chips, semi-sweet chocolate flavor.

Tags: Diets and Weight Loss, Nutrition

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FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.