The U.S. Department of Agriculture describes five main food groups in discussing food choices and guidelines, in order to encourage healthy dietary choices among Americans: vegetables, fruits, grains, protein foods and dairy. Although legumes are vegetables, certain legumes also are considered part of the protein foods group. As the USDA describes it, "Beans and peas are unique foods."
Vegetables
The USDA divides vegetables into five subgroups, including dark green vegetables, beans and peas, starchy vegetables, red and orange vegetables, and other vegetables. Young, fresh legumes that are high in complex carbohydrates, including green lima beans and all varieties of fresh green peas, are classified as starchy vegetables. Bean sprouts, green beans, wax beans and other immature edible-pod beans are in the other vegetables subgroup, while the beans and peas subgroup includes mature legumes, otherwise known as dried beans, peas and lentils. This last group is what most people think of when they think of "legumes." Mature legumes tend to be higher in protein, fiber, iron, magnesium and folate than immature, fresh legumes.
Protein Foods Group
The USDA also divides protein foods into categories, including meats, poultry, seafood, eggs, nuts and seeds, processed soy products, and beans and peas. The beans and peas included in the protein foods group are the same as the beans and peas group of vegetables: these are nutrient-dense, fully mature beans, peas and lentils used in dried form and out of the pod. Black-eyed and split peas, all types of lentils, and kidney, garbanzo, navy, adzuki, cannellini and black beans are examples of mature legumes.
Vegetable Intake
According to the latest USDA MyPlate guidelines, most women age 50 and younger need 2 1/2 cups of vegetables each day, and most men age 50 and younger need 3 cups; adults over 50 can reduce their daily intake by 1/2 cup. Although it’s not important to eat vegetables from each subgroup every day, the USDA does recommend that women age 50 and younger eat 1 1/2 cups of legumes each week, and that men age 50 and younger eat 2 cups; again, adults over 50 can reduce their intake by 1/2 cup.
Protein Intake
With small variations depending on age and gender, most healthy adults require between 5.5 and 6.5 ounces of protein per day, according to USDA recommendations. A small amount of mature legumes makes a significant contribution toward your daily protein requirements. A 1/4-cup serving of cooked dried beans, peas or lentils counts as 1 ounce of protein toward your total daily intake, and 1 cup of bean, split-pea or lentil soup counts as 2 ounces of protein. You can count a serving of mature legumes as either a serving of protein or a serving of vegetables, but not both.
