Eating cooked tubers provides a high caloric content due to the presence of starch, a polymer of glucose that is easily digestible and converted into energy by the body. In contrast, spinach contains cellulose, another polymer of glucose, which is not digestible by humans and therefore contributes negligible calories. Despite its low caloric value, spinach is considered healthy because it is rich in vitamins, minerals, and antioxidants, providing essential nutrients without excess calories. The differing properties of starch and cellulose highlight why tubers are energy-dense while leafy greens like spinach are nutrient-dense, making them both valuable in a balanced diet.
