Diet During Cancer Treatment: What to Eat and What to Avoid

When someone in the family is diagnosed with cancer, the questions about food begin straight away. What should they eat? What should they avoid? Is there a special diet that fights cancer? The honest answer is that no food cures cancer, but good nutrition during treatment really does matter. People who eat well keep their strength, cope better with chemotherapy and radiotherapy, and recover faster. This guide covers practical, everyday eating advice that suits desi kitchens.

Why nutrition matters

Cancer and its treatment can cause loss of appetite, nausea, taste changes, mouth sores, diarrhoea or constipation, and quick weight loss. Losing muscle and weight makes treatment harder to tolerate. The goal is not a perfect diet, but to eat enough protein and energy, drink enough fluid and keep weight steady.

Eating well when appetite is low

• Eat small meals every two to three hours instead of three large ones.
• Eat by the clock, and do not wait to feel hungry.
• Make every bite count by adding energy and protein: a spoon of ghee or butter in khichdi, daliya or mashed potato, milk powder in soups and kheer, and dahi or paneer with meals.
• Good protein foods include eggs, daal, chana, chicken, fish, milk, dahi, lassi, cheese, almonds and peanut butter.
• Nourishing drinks help when food is hard to eat. Try milkshakes with banana, dates and almonds, badam milk, soup, or a glass of lassi.
• Keep favourite snacks within reach, and eat in a calm, pleasant place with family.
• Light activity, such as a short walk, can lift appetite.

Coping with common side effects

Nausea and vomiting

• Choose plain, dry foods such as toast, rusk, plain roti and rice
• Cold or room-temperature food smells less than hot food
• Sip ginger tea or cold water through the day
• Avoid greasy, spicy and very sweet food, and strong cooking smells

Mouth sores and a sore throat

• Choose soft, cool, bland foods: khichdi, mashed banana, custard, yoghurt, soup
• Avoid spicy, sour, salty and very hot food, and crunchy or sharp items
• Rinse your mouth with plain water or salt water as advised

Changes in taste

• If food tastes metallic, try cold food and plastic cutlery, and add lemon, mint or herbs
• Brush your teeth and rinse before eating

Diarrhoea

• Drink plenty of fluids, including ORS, to replace losses
• Eat bananas, rice, dahi, boiled potatoes and toast, and avoid fried, spicy and very fatty food

Constipation

• Drink fluids and eat fibre as tolerated, such as prunes, papaya, and whole-wheat roti, and take a short walk

Food safety matters more during treatment

Chemotherapy can lower your defences against infection. Ask your oncologist if you need extra precautions, which commonly include:

• Washing hands before cooking and eating
• Cooking meat, chicken, fish and eggs thoroughly
• Washing fruit and vegetables well, or peeling them, and avoiding raw salads when your counts are low
• Drinking boiled or properly filtered water, and avoiding unpasteurised milk
• Avoiding street food, open cut fruit and food left out for hours

Supplements, herbs and cancer myths

• No food or herb cures cancer. Be wary of anyone who sells a special diet, juice or herbal product as a cure.
• Always tell your oncologist about every supplement, herbal remedy, haldi capsule or “detox” product. Some interfere with chemotherapy or radiotherapy, or harm the liver and kidneys.
• High-dose antioxidant supplements are not advised during treatment unless your oncologist agrees.
• Sugar does not feed cancer faster than other cells, and starving yourself of food does not starve the cancer. It only weakens you.
• Severe restriction or extreme diets, such as fasting or only juices, can cause dangerous weight loss.
• Ask for a referral to a dietitian who treats cancer patients. It makes a real difference.

Medicines that can help with side effects

Your oncologist may prescribe anti-sickness medicines before and after chemotherapy, and may suggest ORS, laxatives or mouth rinses. Please take medicines for side effects only as directed. For example, anti-diarrhoea tablets should only be used if your team says they are safe, because diarrhoea during chemotherapy can sometimes signal infection.

When to call your doctor

• You cannot keep down food or fluids for more than a day
• Severe or persistent diarrhoea, or signs of dehydration such as dizziness and very little urine
• You are losing weight quickly
• Fever of 38°C or above during chemotherapy, which needs urgent attention
• Mouth sores so painful that you cannot eat or drink

Key takeaways

• No diet cures cancer, but good nutrition helps you tolerate treatment.
• Small, frequent, protein-rich meals and nourishing drinks work best when appetite is low.
• Keep to simple, safe, well-cooked food, and drink boiled or filtered water.
• Tell your oncologist about every supplement or herbal remedy before using it.

Related medicines on Medimart

These are commonly used to manage side effects of cancer treatment. Use them only as directed by your oncology team.

• Ondansetron: helps control nausea and vomiting from chemotherapy
• Domperidone: eases nausea and fullness
• Metoclopramide: helps with nausea and slow stomach emptying
• Oral rehydration salts (ORS): replace fluids lost to diarrhoea or vomiting
• Lactulose: a gentle laxative for constipation
• Benzydamine: eases a sore mouth and throat

Prescription medicines are supplied only against a valid prescription. Please take them only as advised by your doctor.

Browse cancer care products and nausea and vomiting relief on Medimart with delivery across Pakistan. Prescription medicines are supplied only against a valid prescription.

This guide is for general information and does not replace advice from your oncologist or dietitian. Please check any diet change or supplement with your cancer team.