Foods do not have therapeutic properties or effects, and there is no such thing as the best food to protect the heart, but reduced cardiac function can be maintained on a diet low in salt, low in fat, low in sugar, and high in fiber. 1. Low-salt food: daily salt amount is controlled below 6g to avoid excessive sodium intake to increase the burden on the heart. You can eat porridge and boiled vegetables. 2. Low-fat food: Try to consume lean meat portion of meat, you can eat fish, chicken breast, beef and so on. 3. Low-sugar food: too much sugar intake causes obesity will increase the burden on the heart, you can eat foods with low sugar content, such as grapefruit, oranges, cucumbers, tomatoes, pumpkins, winter squash and so on. 4. High-fiber foods: eat more corn, sweet potatoes, etc., to increase the intake of dietary fiber. In addition to a balanced diet, you should also exercise in moderation and develop healthy and regular living habits to better protect your heart. It is recommended to consult your doctor and choose foods under professional guidance.