Foods with fat substitutes might have fewer grams of fat, but they don't necessarily have significantly fewer calories, warns a Cornell University nutrition expert. In fact, she asserts, many people consume as many calories overall even when they eat reduced-fat or sugar-free foods, or both.

"In many cases, people add these foods to their diets, rather than substitute them for high-fat or high-sugar foods," Christina Stark, a Cornell Cooperative Extension nutrition specialist in the Division of Nutritional Sciences, told nutrition educators recently. "In fact, some people tend to eat larger servings when they know a food is fat-free, perhaps forgetting that fat-free doesn't mean calorie free."

When foods such as reduced-fat, fat-free or sugar-free sodas, cookies, chips and crackers are added to the diet, they also tend to take the place of more nutritious foods that are packed with vitamins, minerals and fiber. "Unfortunately, substituting fat and sugar with alternatives doesn't substitute for bad eating habits," said Stark.

Her audience was part of a group of 300 nutrition educators who were on Cornell's campus June 15-16 for the 30th anniversary celebration of the Expanded Food and Nutrition Education Program (EFNEP).

Although fat-free and sugar-free snack foods are fine in moderate quantities, Stark pointed out that their consumption might undermine the eating of more healthful diets and falsely lead some dieters into thinking that simply choosing fat-free or sugar-free foods will help them lose weight.

Many reduced-fat and fat-free snack foods are only about 10 calories less per serving than their full-fat counterparts. Stark demonstrated this fact with food labels from numerous products (see chart). In one case (pudding mix), the calorie content was identical. She also said several studies with reduced-fat foods have shown that some people tend to make up the fewer calories in those foods by eating more of other foods.

Stark pointed out that in recent years Americans have succeeded in reducing their percentage of calories from fat to about 33 percent from almost 40 percent 20 years ago. However, in the same time period, which coincides with the introduction of more low-fat foods, the percentage of overweight Americans has climbed to 33 percent from 25 percent. Regardless of the fat content of the diet, eating more calories than you need will still lead to weight gain. Recent federal clinical guidelines, which use a revised definition of overweight, suggestmore than 50 percent of American adults are overweight or obese.

Stark recommended that, in general, people should reduce the fat and calorie content of their diets by eating more naturally low-fat foods like fruits and vegetables and grain products, and by modifying recipes and cooking methods, rather than relying on products containing fat and sugar substitutes.

COMPARING FOODS WITH THEIR FAT-FREE COUNTERPARTS