My impression was that all fabas (favas) are legumes, but not all legumes are fabas. I read that about 4% of the world population has an enzyme deficiency that causes fava beans to provoke a potentially fatal hemolytic anemia if they are eaten, raw or cooked. These people don't react the same way toward other types of legumes. would think that in itself would be a good argument for not calling all beans fabas.
