Rheumatic heart disease often occurs in people with lower resistance, making them susceptible to colds and fevers. Their diet should include foods that enhance immune and disease resistance, such as lean meats, fish, and seafood, which are high in protein, along with milk and eggs. Eating fruits that are rich in vitamins and fibers, like apples, avocados, oranges, and dried fruits, as well as consuming more vegetables, can strengthen the body's resistance and provide various vitamins and trace elements needed by the human body.