A diet that maintains health while fighting cancer includes protein, carbohydrates, fat, water, vitamins and minerals. The role of these nutrients is discussed below.


Protein helps to ensure growth, to repair body tissue and to maintain a healthy immune system. A diet poor in protein can lead to longer recovery from illness and lower resistance to infection. Surgery, chemotherapy, and radiation therapy may increase your body’s need for protein. Good sources of protein include lean meat, fish, poultry, dairy products, nuts, dried beans, peas and lentils.

Carbohydrates and Fats

These are the nutrients that provide the fuel (calories) your body needs. The amount of calories each person needs depends on age, size and physical activity. Sources of carbohydrates include fruits, vegetables, breads, pasta, grains and cereal products, dried beans, peas and lentils. Sources of fat include butter, margarine, oils, nuts, seeds, and the fat in meats, fish and poultry.

Vitamins and Minerals

Vitamins and minerals ensure proper growth and development. They also allow the body to use the energy (calories) supplied in foods. A balanced diet with enough calories and protein usually provides enough vitamins and minerals. Sometimes, you may find it hard to eat a balanced diet when receiving cancer treatment. If this persists, the doctor or dietitian may recommend a daily multivitamin and mineral supplement.


Water and fluids are vital to health, including immune function. If you are not able to drink enough fluids because of treatment side effects such as vomiting or diarrhea, you may become dehydrated. Your healthcare team can help you manage these side-effects and provide guidelines on how much fluid is needed each day to prevent dehydration.