Diet Choices When You Have Cancer

Medically Reviewed by Sabrina Felson, MD on March 09, 2023
3 min read

When you have cancer, the disease and its treatment might make you feel tired and weak. But eating the right foods can help.

There's no specific diet for people with cancer. But certain eating patterns can support your immune system -- your body's defense against germs -- and give you strength and energy. They may ease the side effects of treatment.

Nutritious foods can encourage your body to heal faster. They can also help you keep to a healthy weight and lessen the chance of getting other illnesses and heart disease.

Try these steps to help manage symptoms and feel your best while living with cancer.

Fill your plate with fruits and vegetables. They contain the vitamins and minerals that your body needs to work right. Fruits and veggies also deliver antioxidants, which protect against cell damage and inflammation. Aim to get five to 10 servings of produce each day.

For the biggest benefit, have a wide variety of fruits and veggies. Make at least one serving a cruciferous vegetable, such as broccoli, cabbage, or kale. One study done on cells in a lab suggests that a compound in these veggies, called sulforaphane, may help fight certain leukemia cells.

Get enough protein. Your body uses protein to repair tissue and keep your immune system healthy. Without enough protein, it uses muscle for energy. This can rob you of strength and raise your chances of infection. It can also slow down your recovery.

You may need extra protein after surgery, chemotherapy, or radiation therapy. Good sources include fish, lean beef, poultry, eggs, low-fat dairy, nuts, beans, and tofu.

Choose healthy fats. Fat helps keep your body warm and helps send key nutrients throughout your body. But some fats are better than others. Saturated fats, found mostly in animal products like full-fat dairy and meat, raise your risk for heart disease.

Get most of your fat from healthy unsaturated fats, such as those in vegetable oils and seafood. Research suggests that the omega-3 fats found in fish may curb cancer cell development

Drink plenty of fluids. Your cells need water to work properly. When you don't drink enough, you become dehydrated. This can make you tired, dizzy, and confused. You may get a headache. Drinking up can help ease symptoms of cancer, such as constipation and fatigue. Certain cancer treatments like radiation and chemotherapy have side effects, such as nausea and diarrhea, which can also lead to dehydration.

You need roughly 8 cups of water every day, but check with your health care team. They may recommend a drink, such as a sports beverage or broth, to replace electrolytes. To get enough fluids, don't wait to drink until you're thirsty. Sip regularly.

Cut back on processed foods. They're often high in sodium, sugar, and unhealthy saturated fat. They can alter your gut bacteria, which, in turn, triggers long-term inflammation.

This inflammation may play a role in the development of cancer. 

Limit your alcohol. Drinking too much alcohol can contribute to dehydration. It can also irritate any mouth sores caused by treatment. Over the long run, alcohol may damage cells and raise your odds of certain cancers, such as liver, breast, and mouth cancers. 

Talk to your doctor about drinking alcohol. Even moderate amounts may affect how well your bone marrow works, which can have an impact on your treatment.

Pay close attention to food safety. Your cancer treatment may weaken your immune system and raise your chances of getting foodborne illness. These steps can help keep you safe:

  • Cook meat until it's well-done and eggs until the yolks are hard.
  • Avoid raw sprouts, salad bars, and unpasteurized drinks and cheeses.
  • Wash fresh fruits and vegetables.

Your health care team may suggest that you follow additional guidelines or a "neutropenic diet," which is meant to limit your exposure to potentially harmful bacteria and other organisms in food.  

Eat to manage your treatment side effects. Treatments, including chemotherapy and radiation therapy, can affect the way you eat and drink. Your appetite and senses of taste and small may change. You may have a dry mouth or mouth sores. Or you may struggle with diarrhea, nausea, or constipation.

You may need to change your diet to deal with these side effects. Steps may include:

  • Eat four to six small meals each day instead of three large ones.
  • Keep high-calorie, high-protein snacks and small meals on hand.
  • If food tastes bland, season your dishes with spices rather than salt.
  • When dealing with mouth sores or a sore throat, steer clear of acidic or spicy foods.