When people hear the word "protein," the first food that often comes to mind is meat. some people believe that they cannot obtain sufficient protein unless they eat meat. there are, however, many dietary sources of protein, both animal and plant. from the list below, choose all the correct statements about dietary sources of protein. select all that apply. select all that apply. because it is so difficult to obtain enough protein from foods, most athletes need amino acids supplements to meet their increased protein requirements. although soybeans and foods made from soybeans (such as soy milk and tofu) are good sources of protein, the quality of soy protein is far inferior to that of meat. a serving size of peanut butter (2 tbsp) has about the same amount of protein as 1 oz of meat. skim milk and whole milk have a similar protein content. combining grains (such as rice or corn) with legumes (such as black beans or lentils) provides the body with a complete protein. all grains are sources of incomplete protein.