Food Safety During Cancer Therapy

While undergoing chemotherapy or radiation therapy, or in the period shortly after receiving therapy, food safety is very important, as your immune system may be weakened and, therefore, not as protective as it normally is.

> Download the latest Food Safety for People with Cancer brochure from the USDA/FDA

If you recently have undergone a transplant or if your white blood cell count is very low, it is extremely important to follow food safety guidelines. A good guideline to follow is to eat only those foods that have been freshly prepared in a clean environment and which have not been sitting out for any length of time. If you'd like to speak to dietitian Natalie Ledesma about your concerns, you can schedule an appointment through the UCSF medical practice where you are being seen. The following recommendations have been adapted from patient guidelines provided at the Fred Hutchinson Cancer Research Center.

Grocery Shopping

  • Check "sell by" and "use by" dates and do not buy items that are out of date.
  • Do not buy or use any bulging, damaged, or deeply dented cans.
  • Make sure that frozen foods feel solid and that refrigerated foods are cold.
  • Do not buy cracked or unrefrigerated eggs.
  • Store groceries promptly after shopping
  • Do not buy bulk foods from self-service bins.

Food Preparation

  • Prepare food on surfaces that have been thoroughly washed in hot, soapy water. You can clean cutting boards in a solution of ten parts water mixed with one part household bleach.
  • Use separate cutting boards for cooked foods and raw foods.
  • Do not use raw, unpasteurized eggs in uncooked foods, since raw eggs are the perfect medium for the growth of bacteria such as salmonella.
  • Discard eggs, egg mixtures, or prepared egg dishes left at room temperature for more than an hour.
  • Wash the tops of cans and the can opener before use.
  • All meats should be cooked until well-done and should have no remaining pink color.
  • Foods should be cooled inside the refrigerator rather than outside. A good way to do this is to divide large amounts of hot food into small, shallow containers for quick cooling in the refrigerator.
  • Do not eat perishable foods that have been left out of the refrigerator for more than two hours.
  • Do not eat foods that have been sitting in the refrigerator for more than three days. A helpful way to keep track is to put a date on prepared foods and other perishable, refrigerated items once they have been opened. It is also helpful to refrigerate only the amount of food that you will eat in two or three days and freeze the rest.
  • Thaw meats and fish in the refrigerator.
  • Throw away food that has any mold on it.
  • Never taste foods that look or smell strange.
  • Wash and rinse fruits and vegetables thoroughly before eating them.

Foods to Avoid

The following section provides a list of foods that are more likely to carry infection-causing organisms. In addition to the foods listed here, there may be other foods that your transplant center recommends that you avoid. In order to get a full listing of foods to avoid, make sure to discuss food safety guidelines thoroughly with your dietitian or medical provider.

  • Free food samples.
  • Foods at potluck meals where you don't know how food was prepared or how long it was sitting out of the refrigerator.
  • Food from sidewalk vendors, delicatessens, smorgasbords, buffets, and salad bars.
  • Soft-serve ice cream, milk shakes, and frozen yogurt from yogurt machines.
  • Sushi, raw fish, and smoked fish.
  • Raw eggs, Caesar salads containing raw egg, mayonnaise-based foods, custards, or other dishes that may contain raw eggs.
  • Wellwater unless it has been tested and found to be safe.
  • Unpasteurized honey, milk, cheese, and yogurt.
  • Unrefrigerated cream.
  • Unroasted nuts or nuts in the shell.
  • Aged cheeses such as certain sharp cheeses.
  • Moldy cheeses such as brie and blue cheese.

Discuss the use of vitamin/mineral supplements with your physician and dietitian, as they may interfere with various medications or may be harmful to major organs, especially the liver and kidneys. Be cautious if you are using nontraditional nutrition supplements, such as herbal preparations, as they may contain toxic impurities or infection-causing fungi, yeast, molds, or bacteria. These can be life threatening for a person with a weakened immune system.


For additional information or resources, please visit the Cancer Resource Center at 1600 Divisadero Street on the first floor, or call (415) 885-3693.

The information in this publication is designed for educational purposes only and is not intended to replace the advice of your physician or health care provider, as each patient's circumstances are individual. We encourage you to discuss with your physician any questions and concerns that you may have.

Ida & Joseph Friend Cancer Resource Center [Reprints Require Permission]