Despite the name, butter beans are quite different from butter -- they contain no fat and are rich in carbohydrates and fiber. Butter beans are also rich in protein, which may make them beneficial for inclusion in a vegetarian diet as a protein source.
According to the nutrition information from MyFitnessPal, each 1/2 cup serving of butter beans contains 90 calories. If you base your daily calorie intake on the suggested level of 2,000 calories, then one serving of butter beans provides 4.5 percent of your daily intake. The calorie expenditure information at MayoClinic.com indicates you could burn off those calories through about half an hour of walking at a 2 mph pace.
The nutrition information at MyFitnessPal notes that the main source of calories in butter beans is the carbohydrates. Each 1/2 cup serving contains 19 g of carbohydrates. Of these carbohydrates, 5 g come from fiber. The National Library of Medicine and National Institutes of Health explain that fiber is a vital nutrient that aids in digestion and keeps you feeling full.
Each 1/2 cup serving of butter beans provides 5 g of protein, according to MyFitnessPal. Protein is essential for supporting the structure of your body's tissues.
Butter beans do not contain fat, according to the nutrition information at MyFitnessPal. However, cooking beans with butter, oil or other sauces may add fat, so check nutrition labels when possible.