Is It Safe to Eat Out During Cancer Treatment?

The reason is specific, and NCI states it plainly. Some cancers and some treatments lower the number of white blood cells. Those cells fight infection.

There is a rhythm to it. During chemotherapy there are points in each cycle when neutrophils, the infection-fighting white cells, are particularly low. Blood tests check for that. Medicine is sometimes given to prevent infection or to push the count back up.

So the question is not really whether restaurants are safe. It is that the margin for error narrows, and it narrows more at some points in the month than others. FDA thought this mattered enough to publish a booklet for people with cancer, with a section on eating out. See also infection and neutropenia.

FDA's rules are short enough to memorize:

• Ask whether a dish contains uncooked ingredients such as eggs, sprouts, meat, poultry or seafood. If in doubt, choose something else.
• Do not order meat cooked rare.
• Ask how the food was cooked. If the server does not know, ask to speak to the chef.

FDA also suggests telling the server directly that no dish should contain raw meat, poultry, seafood, sprouts or eggs. That single sentence does most of the work, because it covers the dressing, the garnish and the sauce as well as the main item. Caesar dressing made with raw egg is the classic example. FDA notes that pre-made versions from a grocery store, labeled as made with pasteurized eggs, are lower risk than a house-made one.

FDA adds a fourth line that is easy to miss. Servers can be quite helpful if asked. The booklet frames this as a normal request, not a special favor.

These are the numbers behind "well cooked." FDA and USDA publish them together:

• Ground beef, pork, veal and lamb: 160 °F.
• Ground turkey and chicken: 165 °F.
• Steaks, roasts and chops of beef, veal or lamb: 145 °F, then a 3-minute rest.
• All poultry, whole or in pieces: 165 °F.
• Fresh pork and fresh ham: 145 °F, then a 3-minute rest.
• Precooked ham being reheated: 140 °F.
• Egg dishes: 160 °F. Plain eggs: cook until yolk and white are firm.
• Leftovers and casseroles: 165 °F.
• Fin fish such as cod, snapper or tilapia: 145 °F, or until the flesh is opaque and separates easily with a fork.
• Shrimp, lobster and crab: until the flesh is pearly and opaque. Scallops: until milky white or opaque and firm. Clams, oysters and mussels: until the shells open.

Two holding temperatures matter as much as the cooking ones. Cold food belongs at 40 °F or below. Hot food belongs at 140 °F or above. That is the real argument against a buffet tray that has been sitting out.

FDA sets these out as pairs, higher risk beside lower risk:

• Soft cheese made from unpasteurized milk, against hard or processed cheese, or soft cheese clearly labeled as made from pasteurized milk.
• Refrigerated smoked seafood, and raw or undercooked seafood such as sashimi, non-vegetarian sushi or ceviche, against fully cooked fish that is firm and flaky.
• Cold or poorly heated hot dogs, against hot dogs reheated until steaming.
• Sandwiches with cold deli or luncheon meat, against grilled sandwiches where the meat is heated until steaming.
• Soft-boiled or over-easy eggs, because the yolk is not fully cooked, against eggs with firm yolk and white.
• Raw sprouts of any kind, against cooked sprouts.

The deli meat rule has a reason worth knowing. Listeria monocytogenes keeps growing at refrigerator temperatures of 40 °F or below. Reheating until steaming, or to 165 °F, destroys it. That is why a cold sandwich and a hot one are not the same decision here.

Unwashed fresh vegetables, including bagged salads, sit on the higher-risk side too. NCI's version of the advice is that people may be told to eat only fruits and vegetables that can be peeled, or to wash all raw produce very well. Which of those applies is a question for the care team, since centers differ.

FDA gives one number for taking food home. Refrigerate perishable leftovers as soon as possible, and always within two hours of purchase or delivery. If it is above 90 °F outside, that drops to one hour.

Reheating has its own rule. Bring sauces, soups and gravy to a boil. Heat other leftovers to 165 °F.

NCI lists nine signs of infection during cancer treatment:

• A temperature of 100.4 °F (38 °C) or higher.
• Chills.
• Cough or sore throat.
• Diarrhea.
• Ear pain, headache or sinus pain, or a stiff or sore neck.
• Skin rash.
• Sores or a white coating in the mouth or on the tongue.
• Swelling or redness, especially where a catheter enters the body.
• Bloody or cloudy urine, or pain on urinating.

The fever number is worth a footnote. NCI's page, reviewed in January 2020, uses 100.5 °F. CDC's page on fever during chemotherapy, updated in November 2024, uses 100.4 °F (38 °C). A care team's own threshold overrides both.

NCI adds one warning that gets missed. Talk to a doctor or nurse before taking anything for a fever, including aspirin, acetaminophen or ibuprofen. Those drugs bring the temperature down and can hide a more serious problem underneath.

FDA lists the symptoms of foodborne illness itself as nausea, diarrhea, vomiting, fever and abdominal cramps. Its instruction for anyone with a weakened immune system is to contact a healthcare provider immediately, and to keep the food.

• https://www.fda.gov/media/83744/download
• https://www.cancer.gov/about-cancer/treatment/side-effects/infection
• https://www.cdc.gov/cancer-preventing-infections/patients/fever.html