as per the usda, you can count beans as either a protein or a vegetable. for people who eat little to no meat, they should start by counting beans as protein. for people who eat plenty of meat, they can start with either. keep in mind that the greatest benefit from veggies is from getting different vitamins and minerals and the best way to ensure that variety is to eat the rainbow. so getting all your veggie servings from beans wouldn't do you very much good.
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