Whole grains are recommended over refined grains because they retain more nutritional value, including fiber, vitamins, and minerals. Whole grains provide essential nutrients and help regulate blood sugar levels, promoting better digestive health and reduced risk of heart disease. The fiber content in whole grains aids in digestion and promotes a feeling of fullness, which can assist in weight management. In contrast, refined grains often lack these benefits and can lead to increased cravings and overeating.