The short answer
Some treatments weaken the immune system, making food-borne illness more likely and more serious. Safe food handling — clean, separate, cook, and chill — and avoiding higher-risk foods like raw or undercooked items may help lower the risk.
Some treatments weaken the immune system, raising the risk of food-borne illness.
The basics: clean, separate, cook, and chill.
Avoid raw or undercooked meat, eggs, and seafood, and unpasteurized foods.
Wash hands, produce, and surfaces well, and keep hot foods hot and cold foods cold.
Choose how you want to understand this
The full explanation.
The simple version
Some cancer treatments make it harder for your body to fight germs. Food safety then matters more than usual, because food-borne illness can hit harder. A few simple habits lower the risk.
The four basics
The core food-safety steps are easy to remember:
- Clean. Wash hands, produce, utensils, and surfaces well.
- Separate. Keep raw meat, poultry, and seafood away from other foods.
- Cook. Cook foods to safe temperatures. A food thermometer helps.
- Chill. Refrigerate leftovers promptly, and keep cold foods cold.
Foods to be careful with
During treatment, it often helps to avoid higher-risk foods:
- Raw or undercooked meat, poultry, eggs, and seafood.
- Unpasteurized milk, juice, and soft cheeses.
- Raw sprouts.
- Foods that are past their date or left out too long.
Ask your care team — precautions depend on your treatment and blood counts.
A note before we begin
This information is educational. It is not a substitute for medical advice. For your own care, talk with your doctor, nurse, pharmacist, registered dietitian, or care team.
When to get help sooner
Food poisoning hits harder when treatment has weakened your immune system. Ask your team now what number to call at night and on weekends.
- Call 911 or go to an emergency department if you feel confused or faint, or you have severe belly pain.
- Phone your care team immediately, at any hour, if your temperature reaches 100.4°F (38°C) or higher while you are on treatment that lowers your blood counts. CDC calls a fever during chemotherapy a medical emergency. If you cannot get through quickly, go to an emergency department and tell them at once that you are on chemotherapy.
- Call your care team the same day if you cannot keep fluids down, you see blood in your stool or vomit, or you are passing very little urine.
- Call your care team within a day or two if vomiting or diarrhea keeps going, or you feel weak and dizzy when you stand.
Sources
Words to know
Tap any term to see what it means.
Common questions
Why does food safety matter more during treatment?
Some cancer treatments lower the body's ability to fight germs. That makes food-borne illness (food poisoning) both more likely and potentially more serious. Extra care with food can help lower the risk.
What are the basic food-safety steps?
Four simple habits: Clean (wash hands, produce, and surfaces), Separate (keep raw meats away from other foods), Cook (cook foods to safe temperatures), and Chill (refrigerate promptly and keep cold foods cold).
Which foods should I be careful with?
It often helps to avoid raw or undercooked meat, poultry, eggs, and seafood; unpasteurized milk, juice, and soft cheeses; raw sprouts; and foods past their date. Ask your care team for advice for your situation.
How do I know if I need extra precautions?
Ask your care team, especially if your blood counts are low or you're at higher risk of infection. They can tell you which precautions apply to you and for how long.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
Tap a question to save it to your list (kept on this device).
Speak With Trained Specialists & Human Navigators
Cancer Explained provides educational guidance, but does not replace trained specialists, social workers, or your medical team.
Talk to a trained cancer information specialist
Free, confidential assistance from NCI Cancer Information Service via phone, chat, or email.
Contact your oncology team
Locate after-hours contact numbers, portal messages, or urgent triage phone lines.
Find a patient navigator
Get one-on-one help with appointments, logistics, translation, and care coordination.
Find a genetic counselor
Discuss inherited mutation risk, family history, and genetic testing options.
Find an oncology social worker
Access emotional counseling, family support groups, and mental health resources.
Find a financial navigator
Locate copay assistance foundations, grant programs, and lodging/travel support.
Find a clinical-trial specialist
Search matching studies and speak with NCI trial information specialists.
Get urgent help
Immediate emergency guidance for fever (>100.4°F during chemo), severe pain, or shortness of breath.
Help Us Improve This Guide
Did this explanation answer your question and help you determine your next step?
Know someone who needs this?
Plenty of people are looking for something like this and do not know where to start. If this would help a friend or someone you love, send it on — we have written an opening line so you do not have to stare at an empty message. You can change every word of it.
Your message is written and sent in your own email or messaging app — we never see who you send it to, and nothing is added to any list.
Knowledge Check
0 of 3 answered
This self-assessment checks understanding of educational content only. It is not medical advice.
Plain-language explanation of the published sources cited on this page. AI-assisted, source-checked, not clinician-reviewed.
Last updated: 2026-08-18Next planned review: 2027-07-07
How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status — Source checked. This page was written with AI assistance and checked line by line against the sources listed on it. That confirms the sources support what the page says. It is not a medical review, and it does not confirm the page is complete or right for your situation.
General education — varies by person. Answers genuinely differ between people. This page explains what commonly varies and points you to your care team for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
How this page was created
Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and checked line by line against the sources listed on it. That confirms the sources support what the page says. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
Read more about our editorial process, our use of AI, and our corrections policy.
Spotted a problem? Report an error — a factual mistake, broken or outdated source, confusing wording, or anything that seems unsafe. Please do not include names, medical record numbers, dates of birth, addresses, or other identifying medical information in your report.
After using this page, do you understand what to do next?
Anonymous — we only record the answer, never who gave it.
Related articles
Still have questions?
Educational answers, plain language
Free to print and share