Because its main ingredient is soybeans, miso is full of high-grade protein. In addition, soybean fat is believed to prevent the accumulation of cholesterol on artery walls. There are many types of miso, but they are generally divided into two categories, "red" and "white," based on color. Red miso generally is dark brown with a distinct aroma and flavor, whereas white miso tends to be lighter and sweeter. Both are used in soups and spread on grilled eggplant.