A new report on American's eating habits reveals that almost a quarter of the calories we consume come from nutrient-poor selections, otherwise known as junk food.

The report is based on surveys of 4,700 people. According to responses, soft drinks are the number-one source of calories. Soft drinks accounted for 7.1% of calories consumed by respondents in 1999 and 2000. Altogether, categories of soft drinks, sweets and desserts and alcoholic beverages contributed 23.8% of the calories consumed by survey respondents. Salty snacks and fruit-flavored drinks added another 5% of calories.

Another study looking at youths ages 8 to 18 reported similar findings. Candy, table sugar, sweetened drinks, baked and dairy desserts, salty snacks, fatty foods like butter and gravy, and other nutrient-poor foods made up more than 30% of the calories youths ate. The study also found that youths who ate the most junk food tended to eat the least amount of nutrient-dense, healthful foods.

A third study looked at the impact of salty snack foods, like potato chips, corn chips, crackers, pretzels and cheese curls. Those who ate the most of these high-fat, salty snack foods had diets high in total and saturated fat and low in fruits and vegetables.

The three studies offer some important messages -- between-meal snacks and drinks may be the best place to start substituting healthy choices and cutting back. Also, people who are overweight also can be undernourished. Finally, the studies refute the idea that, as long as someone maintains an appropriate weight, junk food is OK. Eating substantial amounts of high-calorie, low-nutrient foods tends to be part of an eating pattern that ignores nutrient-rich vegetables, fruits, whole grains and beans. Even for those who do not gain weight, the pattern could increase health risks by depriving one's diet of protective nutrients and phytochemicals.