What children with cancer need: Nutrients

Children with cancer need protein, carbohydrates, fat, water, vitamins, and minerals. A dietitian can help you understand your child’s specific needs and develop an eating plan. Your child’s baseline nutritional status (Is he overweight? underweight?), diagnosis, treatment plan, age, activity levels, and current medicines are all used to make a nutrition plan.


The body uses protein to grow; repair tissues; and to maintain the skin, blood cells, the immune system, and the lining of the digestive tract. Children with cancer who do not get enough protein might break down muscle for the fuel their bodies need. This makes it take longer to recover from illness and can lower resistance to infection. After a child has surgery, chemo, or radiation treatments, she may need extra protein to heal tissues and to help prevent infection.

Protein is also key to a child’s growth and development. During illness, a child’s need for protein goes up. Work with your child’s cancer care team to figure out her specific needs at this time.

Good sources of protein include fish, poultry, lean red meat, eggs, dairy products, nuts and nut butters, dried beans, peas and lentils, and soy foods.


Carbohydrates are the body’s major source of energy. Carbohydrates give the body the fuel (calories) it needs for physical activity and proper organ function. How many calories a child needs depends on their age, size, and level of physical activity. Healthy infants, children, and adolescents need more calories per pound than adults to support growth and development. Children being treated for cancer may need even more calories for tissue healing and energy. In fact, a child being treated for cancer may need anywhere from 20% to 90% more calories than a child who is not getting cancer treatment. This varies from child to child, and some kids have a problem with unwanted weight gain during treatment.

The best sources of carbohydrates – fruits, vegetables, and whole grains – give the body’s cells the vitamins and minerals, fiber, and phytonutrients (key nutrients from plants) they need.

    Whole grains or foods made from them contain all the essential parts and naturally occurring nutrients of the entire grain seed. Whole grains are found in cereals, breads, flours, and crackers. Some whole grains can be used as side dishes or part of an entree. When choosing a whole-grain product, look for the words “whole grain,” “stone ground,” “whole ground,” “whole-wheat flour,” “whole-oat flour,” or “whole-rye flour.”

    Fiber is the part of plant foods that, for the most part, the body cannot digest. There are 2 types of fiber. Insoluble fiber takes up space in the intestine, and speeds up the passage of food waste out of the body. Soluble fiber binds with water in the stool to help keep stool soft while it slows down digestion. It can be fermented so that part of it is absorbed.

Other sources of carbohydrates include bread, potatoes, rice, spaghetti, pasta, cereals, dried beans, corn, peas, and beans. These carbohydrate foods also contain B vitamins and fiber. Sweets (desserts, candy, and drinks with sugar) give your child carbohydrates, but very few other nutrients.


Fats play an important role in nutrition. Fats and oils are made of fatty acids and serve as a rich source of energy (calories) for the body. The body breaks down fats and uses them to store energy, insulate body tissues, and carry some types of vitamins through the blood.

You may have heard that some fats are better than others. For the most part, unsaturated fats (monounsaturated and polyunsaturated) should be chosen more often than saturated fats or trans fats.

  • Monounsaturated fats are found mainly in vegetable oils such as olive, canola, and peanut oils. They are liquid at room temperature.
  • Polyunsaturated fats are found mainly in vegetable oils such as safflower, sunflower, corn, and flaxseed oils. They are also the main fats found in seafood. They are liquid or soft at room temperature.
  • Saturated fats (or saturated fatty acids) are mainly found in animal sources, such as meat and poultry, whole or reduced-fat milk, cheese, and butter. Some vegetable oils like coconut, palm kernel oil, and palm oil are saturated. Saturated fats are usually solid at room temperature.
  • Trans-fatty acids are formed when vegetable oils are processed into margarine or shortening. Sources of trans fats include snack foods and baked goods made with partially hydrogenated vegetable oil or vegetable shortening. Trans fats also are found naturally in some animal products, such as dairy products.

Certain fatty acids, such as linoleic acid and alpha-linolenic acid, are called essential fatty acids. They are needed to build cells and make hormones, but because the body cannot make them, we must get them from foods. Soybean, canola, and walnut oils are good sources of essential fatty acids.


Water and liquids or fluids are vital to health. All body cells need water to function. If your child does not take in enough fluids or loses fluids from vomiting or diarrhea, he may become dehydrated (his body doesn’t have as much fluid as it needs). If this happens, the fluids and minerals that help keep the body working can become dangerously out of balance.

Children get some water from foods, especially fruits and vegetables, but they need liquids to be sure that all the body cells get the fluid they need. How much fluid a child needs depends on his size and how much liquid he is losing. Extra fluids may be needed if he is vomiting or has diarrhea. Talk with the dietitian, doctor, or nurse about your child’s fluid needs. Keep in mind that all liquids (soups, milk, even ice cream and gelatin) count toward your child’s fluid goals.

You can see if your child is dehydrated by lightly pinching up the skin over the breast bone. If the skin does not return to normal and stays raised, your child may be dehydrated. Other symptoms include mouth dryness, dark colored urine, listlessness, and dizziness. If you think your child is dehydrated, call the doctor right away.

Vitamins and minerals

The body needs small amounts of vitamins and minerals for normal growth and development, and to help it function properly. Vitamins and minerals also help the body use the energy (calories) it gets from food.

Children who eat a balanced diet usually get plenty of vitamins and minerals. But studies have shown that even healthy kids often don’t get enough calcium and vitamin D, which are especially important for bone growth. Some of the drugs used to treat cancer can lower calcium and vitamin D levels, too, so extra amounts may be needed.

It may be hard for a child getting cancer treatment to eat a balanced diet. Common treatment side effects, like nausea, vomiting, and mouth sores (mucositis) can make it hard to eat. If your child has eating problems, ask your doctor, nurse, or dietitian for help.

The doctor may recommend a daily multivitamin while your child is being treated. But a multivitamin does not replace eating enough calories and protein. Always talk to the doctor before giving vitamins, minerals, or any kind of supplement to your child, since some of them might interfere with cancer treatment.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Revised: June 30, 2014

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