These two books offer an abundance of information about healthy eating:
The Nutrition Bible by Barbara Deskins and Jean E. Anderson
The American Dietetic Association's Complete Food & Nutrition Guide by Roberta Larson Duyff
Instead of the traditional four food groups, the pyramid has five, and they no longer get equal billing. The goal is to eat from the bottom on up:
The base of the pyramid is dedicated to those fiber- and nutrient-rich foods found most effective in maintaining health and fighting illness. The USDA advises choosing most of your calories from foods in the grain group (6 to 11 servings), the vegetable group (3 to 5 servings), and the fruit group (2 to 4 servings).
As you go up the pyramid, the recommended serving sizes go down. More moderate servings of dairy foods (2 to 3 servings) and meat and beans (2 to 3 servings) reflect recent findings on protein requirements and the potential dangers of dietary fat and cholesterol.
At the top of the pyramid is a new group: fats, oils, and sweets. The USDA recommends eating these "sparingly," again reflecting research linking fat intake to heart disease and other health problems.