Yucca, also known as cassava, is a root vegetable that is grown in South America and other regions with subtropical climates. The root of this plant is starchy and is prized in some areas because it is a rich source of carbohydrates.Although yucca root can be a healthy food and may be a staple in some cultures, it's not an ideal diet food, as it is high in calories.Yucca is a poor diet choice because it is high in calories. Each cup of yucca contains 330 calories, 16.5 percent of the 2,000 suggested as a total daily intake for adults.Although you can eat high-calorie food when dieting, it limits the amount of food you can eat in a day.he root of this plant is starchy and is prized in some areas because it is a rich source of carbohydrates. Although yucca root can be a healthy food and may be a staple in some cultures, it's not an ideal diet food, as it is high in calories.