Can I Eat Sushi During Chemotherapy?

The Food and Drug Administration publishes a food safety booklet written for people with cancer and others with weakened immune systems. It sorts foods into higher risk and lower risk.

Raw or undercooked fish — it names sashimi, non-vegetarian sushi, and ceviche — is in the higher-risk column. Fully cooked fish that is firm and flaky is in the lower-risk column.

NCI's infection page says the same thing in fewer words: make sure the meat, fish, and eggs you eat are well cooked. MedlinePlus is blunter still, telling people in cancer treatment not to eat fish, eggs, or meat that is raw or undercooked.

Three federal sources, one direction. Raw fish is the part of a sushi order that carries the risk.

NCI explains the mechanism plainly. Some cancers and treatments such as chemotherapy lower your white blood cells, the cells your body uses to fight infection. During chemotherapy there are stretches in each cycle when one type, the neutrophils, is particularly low.

A germ your body would have cleared without you noticing has a better chance in those weeks. That is the whole reason food safety advice changes during treatment. The food did not get more dangerous. Your margin got thinner.

FDA adds the consequence: with a weakened immune system you are at increased risk of a severe case of food poisoning, not just a worse one.

FDA gives temperatures rather than adjectives:

• Seafood cooked to 145°F is in the lower-risk column.
• Previously cooked seafood reheated to 165°F is also lower risk.
• Canned fish and seafood is lower risk.
• Partially cooked seafood, such as some shrimp and crab preparations, is higher risk.

That last one surprises people. "Cooked shrimp" on a menu is not the same as shrimp cooked through.

Smoked salmon feels cooked. It is not.

FDA lists refrigerated smoked fish in the higher-risk column, in both its home-cooking and its eating-out charts. Cold-smoking does not reach a temperature that kills the germs of concern. If smoked fish is going into a roll or onto a bagel, it belongs in the same category as sashimi for now.

FDA's advice for restaurants is to say what you want out loud rather than guess.

Tell the server you do not want any item containing raw meat, poultry, seafood, sprouts, or eggs. Ask whether a dish contains uncooked ingredients. If the server does not know, FDA says ask to speak to the chef — and if you are still in doubt, order something else.

A sushi restaurant can usually handle this without drama. Fully cooked eel, cooked shrimp, tamago, and vegetable rolls exist for a reason. Ask which items on the menu contain no raw fish.

FDA lists the signs of foodborne illness as nausea, diarrhea, vomiting, fever, and abdominal cramps. Its first instruction if you suspect one is to contact your healthcare provider immediately.

Fever deserves separate emphasis during chemotherapy. CDC tells people in treatment to call immediately at 100.4°F (38°C) or higher and describes a fever during chemotherapy as a medical emergency. NCI's infection page prints 100.5°F next to the same 38°C. Sources word this threshold differently, so use the number your own team gave you.

FDA also suggests keeping the suspect food. Wrap it, label it "DANGER", freeze it, and keep the packaging and receipt. It can help identify what made you ill.

• Do you want me to avoid raw fish for the whole of treatment, or only during low-count weeks?
• When in my cycle is my neutrophil count lowest?
• What is the number I call if I get a fever or vomiting at night?

This is general information. Your care team's specific instructions for your treatment always take priority.

• FDA — Food Safety for Older Adults and People with Cancer, Diabetes, HIV/AIDS, Organ Transplants, and Autoimmune Diseases
• NCI — Infection and Neutropenia during Cancer Treatment
• MedlinePlus — Cancer treatment: preventing infection
• CDC — Fever and Cancer Treatment