Author: Winston Craig, MPH, PhD, RD.
To better manage their weight, an increasing number of people are looking for foods that taste good, yet do not contain too many calories. Studies show that people tend to consume a constant volume of food irrespective of energy or fat content. This suggests that if the fat or energy content of food can be reduced, overall energy intake may also be lowered.
When researchers made a lunch entree more calorie-dense, healthy normal or overweight women, aged 20-44 years, consumed an additional 120 calories for lunch. And yet they reported feeling no less hungry and ate no fewer calories later at dinner time. Clearly, eating foods with a reduced energy density is important for weight management.
But simply removing the fat from a food may not necessarily provide the solution. When fat replacers are used in food, they must replace the functions provided by fat, namely flavor, texture, mouth feel, and volume while providing fewer calories.
Fat replacers have facilitated the development of reduced-fat and fat-free foods which have provided palatable alternatives to high-fat foods. Is there still a need to practice moderation in eating? Absolutely. You can still get too many calories from the over-consumption of low-fat foods.
The use of fat replacers in foods such as mayonnaise, frozen desserts, yogurts, chips, baked goods allow many people to cut their fat intake by one-third and more easily comply with the dietary recommendations that call for a lower fat and lower saturated fat intake. Furthermore, such individuals may be able to cut their calorie intake by up to 200 calories per day. However, the consumer who is concerned with weight management needs to be aware that using low-fat products are not an absolute guarantee for cutting calories since reduced-fat foods are not always reduced in calories.
Fat replacers used in some spreads, margarines, and desserts have the potential to reduce not only calories but also undesirable saturated fat and trans fatty acids for those persons who consume these foods often.
Fat replacers that are carbohydrate-based include modified starches, dextrins, oat fiber, dried plum paste, gums, and polydextrose. These can be used as thickeners for frozen desserts, dairy-type products, spreads and sauces, salad dressings, and baked goods.
Protein-based fat replacers are made from milk or egg protein and are used in low-fat dairy products, baked goods, margarines, mayonnaise, soups and salad dressings.
Some fat replacers may produce physiologically beneficial effects. Some short-term studies have shown weight loss in adults, improvements in blood lipid levels and blood clotting factors among those using reduced-fat products. The use of powdered soluble oat-fiber as a fat replacer has been shown to lower body weight, lower systolic blood pressure, and improve blood lipids and glucose tolerance.
Are All Fat Replacers Safe?
In general, fat replacers can be considered safe when used in moderation. Few health concerns have been raised regarding the adverse effect of fat replacers in our food. However, when used in large amounts polydextrose has a laxative effect while the heavy use of olestra (olean) may cause the loss of some fat-soluble vitamins. Long term studies are needed to evaluate the health effects of these fat replacers. Overall, the use of fat replacers in the diet may play an important role in decreasing fat intake and total energy intake.