Barley has a very high fiber content, vitamins and minerals, antioxidants, heart health and more. Like black rice, it is nutritionally dense and packed with fiber. Therefore, it slows digestion to make those who consume it to feel full for longer while stabilizing blood sugar levels. This would keep the Ancient Romans energized for as long as possible. 

Because of the high fiber in barley, certain cancer risks can also decrease, including colon cancer. Barley is also rich in Niacin, which helps with the metabolism of fats, proteins and carbohydrates.