Food Safety During and After Cancer Treatment

Approved by the Cancer.Net Editorial Board, 08/2021

When food is not prepared or stored correctly, harmful bacteria, parasites, or viruses can grow on the food. Contaminated food can cause foodborne illness, also called "food poisoning", when it is eaten.

Foodborne illnesses can be mild or severe, even for people who do not have cancer. It is important that people with cancer and their caregivers know food safety basics to prevent foodborne illnesses, including:

  • Purchasing fresh food

  • Keeping food fresh

  • Cooking food properly

  • Storing food properly

Talk with your health care team to see if there are specific recommendations based on your cancer treatment plan. Here are some general recommendations on how to avoid foodborne illness.

Food safety tips while grocery shopping

When you are shopping for groceries, follow these suggestions to choose the freshest food and keep it fresh while you shop. Always look at how the food is stored and carefully choose your meat, fruits, and vegetables.

  • Only buy food stored and displayed in a clean area.

  • Choose fruits and vegetables with no bruises or other damage.

  • Put foods that need to be kept cool, like meat, milk, and ice cream, in your grocery cart last.

  • Put any raw meat, poultry, eggs, or fish in their own bag at checkout. Do not put other food in that bag.

  • Choose cans of food with no cracks, dents, or bulges.

  • Do not purchase any food that has a tear in the packaging or that is leaking. Make sure safety seals are intact.

  • Consider bringing a cooler with you to keep foods cold on the drive home. Do not make other stops on your way home from the store.

  • Clean your reusable grocery bags.

Food safety tips at home

When you get home from the grocery store, the way you store and prepare your food is important. Follow these tips to keep your food safe at home.

Keep things clean.

  • Rinse all fresh fruits and vegetables under running water, and dry them with a clean towel or paper towel.

  • Rinse the tops of cans before opening them.

  • Before and after preparing food, wash your hands for 20 seconds with warm water and soap. Pay special attention to areas between fingers and under your nails.

  • Clean your utensils and dishes with hot water and soap.

  • Disinfect your kitchen and cutting boards regularly. One way is to use a small amount of liquid, unscented bleach mixed into at least 1 quart of water. Follow the instructions on the bleach container label for exact instructions on making this cleaning solution.

You should also regularly clean your cooking utensils, kitchen counters, and refrigerator shelves.

Handle meat properly. Raw meat, poultry, and fish can spread bacteria to other foods. Cooking them properly will destroy bacteria.

  • Keep raw meat, poultry (such as chicken and turkey), and fish, and their juices, away from other food.

  • Food safety experts do not recommend washing raw meat or poultry. Cooking it will kill any bacteria. In fact, washing raw meat can spread bacteria to nearby surfaces.

  • If you do wash raw meat or poultry, disinfect your sink and the counter space around your sink carefully.

  • Wash any item that you use for preparing raw foods, including utensils, cutting board, and plates, before you use them for other foods or put cooked meat on them.

  • Do not use the same cutting boards for meat, fish, and chicken as you do for fruits, vegetables, or uncooked foods such as bread and cheese. You may want to use plastic cutting boards for meat, fish, and chicken, so they can go in the dishwasher to be sanitized.

How to cook and store food safely

Make sure that you are cooking and storing your food properly. Follow these rules when cooking and storing food:

Make sure your food is fresh. Eat fresh, canned, and packaged food before the "use by" or "best before" date on the package.

Always cook meat, poultry, and seafood to the right temperature. If meat is not cooked to the right temperature, bacteria can remain on the food. Use a food thermometer to check for a safe internal temperature of all cooked poultry and meat. For instance, a ground beef hamburger should be cooked to at least medium (160˚F or 71˚C). Get a full list of recommended internal cooking temperatures on the U.S. government website of

Chill food promptly. Refrigerate or freeze all food that can spoil within 2 hours after it leaves the grocery store's cooler or freezer. Also, freeze or refrigerate leftover cooked food within the same timeframe. In warm weather, do it sooner. Bacteria can grow on cooked food that is left out too long. Food in the refrigerator should be kept at or below 40˚F (4˚C). Food in the freezer should be kept below 32˚F (0˚C).

Thaw frozen food properly. Thaw frozen food in the refrigerator rather than at room temperature. You can also safely thaw food in frequently changed cold water or in the microwave, but cook it as soon as it thaws.

Store leftovers correctly and make sure they are fresh. Bacteria can grow on leftovers if they are not stored properly. You should eat any leftovers within 3 to 4 days. Throw out older leftovers, even if the food looks OK. Some bacteria, such as Listeria, can grow even on foods stored in the refrigerator if kept too long.

Food safety tips at a restaurant

When eating out at a restaurant, follow this guidance to help keep you safe:

  • Consider avoiding buffets and salad bars. This food tends to sit out for a long time and comes in contact with many people. Someone who has a virus or other germs may touch it.

  • Put any leftover food in a “to-go” container yourself, rather than having the server do it. Refrigerate leftovers as soon as you get home.

  • Choose restaurants that are clean and that are willing to prepare your food as you order it cooked.

Is my water safe to drink if I have cancer?

Some water sources, such as well water, may contain potentially harmful bacteria or chemicals. Regular tap water is fine for healthy people, but it is not tested for people with weakened immune systems. Consider using a water filter to remove germs and chemicals from your water. This makes it safer for you to prepare food and drink the water. Your health care team may have suggestions for cost-effective filters you can use.

What are the symptoms of foodborne illnesses?

Symptoms of getting sick from food (foodborne illness) depend on which germ caused the illness. Symptoms are usually similar to what many people call a "stomach flu."

  • Diarrhea

  • Stomach pain or cramps

  • Nausea

  • Vomiting

  • Fever

  • Headache

  • Muscle pains

You may feel sick any time from a few hours to 10 days after eating contaminated food. Most often, people start feeling sick within the first couple of hours or days after an infection. A few germs, such as hepatitis A, do not cause symptoms for several weeks.

What should I do if I think I have food poisoning while I have cancer?

  • Call your doctor right away. It is important to determine the cause of your symptoms, and early treatment is important.

  • Drink plenty of fluids to stay hydrated.

  • Keep the food (or its package) that you think may have caused the problem. Your doctor may want to know this information or have it examined.

  • If you got sick after eating in a restaurant or other public place, call your local health department. By reporting your problem, you may keep other people from getting sick.

Related Resources

Nutrition Recommendations During and After Treatment

3 Steps to a Clean and Safe Fridge for People With Cancer

4 Steps to Take When There's a Food Recall and You Have Cancer

Meal Trains: Providing Food Safely to People With Cancer

How to Clean Your Home When Caring for Someone With Cancer

More Information

U.S. Department of Health & Human Services: Food Safety