by Suzanne Dixon, M.P.H., M.S., R.D.N.
Since chemotherapy knocks down the immune system, are there any foods you would tell people to avoid during chemotherapy? People are told to avoid grapefruit and grapefruit juice when they’re on certain medicines and some people have been told to avoid green tea.
This question raises two very important issues about which foods are safe to eat during chemotherapy and which ones need to be avoided.
The first issue people receiving chemotherapy have to consider is immune system function and food safety. This is critical for people with a compromised immune system. You may need to avoid certain foods to minimize the risk of food-borne illness.
When people receive chemotherapy, their doctors monitor a type of white blood cell called a neutrophil. Neutrophils are part of the immune system. When neutrophil levels are abnormally low, it’s called neutropenia.
If you have neutropenia, you have a higher risk of infection, so it’s very important to follow safe food handling and cooking practices to minimize infection risk.
- Wash your hands for a full 20 seconds with plain soap and running water immediately after handling raw meat, poultry, seafood, eggs, and unwashed produce. Wash surfaces, cutting boards and utensils after each use.
- Never use the same cutting board and knives for uncooked meat, poultry, and seafood and produce. Many people have one cutting board for raw meat, poultry, and seafood and one for produce. Separate these foods in the refrigerator in clean, sealable bags. Store ready-to-eat foods on shelves above raw meat, poultry, and seafood so nothing drips onto other foods.
- Cook all food to the proper temperature to kill bacteria. Beef, pork, lamb, and veal should be cooked to a minimum internal temperature of 145 degrees F. Ground meat, such as hamburger and sausage, must be cooked to at least 160 degrees F all the way through the meat. Poultry must be cooked to a minimum internal temperature of 165 degrees F.
- Refrigerate perishable foods within 1 hour. Always thaw frozen food on a plate or pan in the refrigerator and never on the counter.
If you have neutropenia, avoid the following foods:
- raw or undercooked meat, poultry, seafood, and eggs
- unpasteurized or raw milk
- unwashed fresh produce
- soft and raw-milk/unpasteurized cheeses
- cold or undercooked hot dogs
- deli meats
- raw sprouts (alfalfa and bean)
Some types of produce, such as lettuce, raw green leafy vegetables, strawberries, and raspberries, are difficult to clean well. You may need to avoid these foods if you have neutropenia.
Ask your doctor, nurse or dietitian for guidance if you are unsure whether a particular food is safe for you.
The second issue people being treated with chemotherapy need to consider is how certain foods may interact with chemotherapy medicines.
- Grapefruit is unusual in that it has the potential to interact with many common drugs, from chemotherapy to medicines used to treat heart disease. So, it’s best to avoid grapefruit and grapefruit juice until chemotherapy is completed.
- Green tea is generally considered safe when consumed in usual amounts — one or two cups per day, unless a person is being treated with Velcade (chemical name: bortezomib), which is used to treat certain types of blood cancer. Studies suggest even small amounts of green tea may reduce the effectiveness of Velcade. It’s important to know that taking green tea supplements is considered unsafe.
Avoid any supplement that contains highly concentrated forms of a food or beverage during breast cancer chemotherapy. These higher amounts of food components have the potential to interact with chemotherapy.
What about supplements? Are there any that should be avoided during chemo?
In general, you should limit the use of most dietary supplements during chemotherapy to minimize the risk of the nutrients interacting with the chemotherapy medicine(s). If you are interested in taking supplements during chemotherapy treatment, talk to your oncologist BEFORE you take anything.
You also should avoid any supplement that contains highly concentrated forms of a food or beverage during breast cancer chemotherapy.
Nausea is a very common side effect of chemo. Are there foods or ways to eat if you feel nauseated? Can probiotics help?
The following tips can help you cope with chemotherapy-associated nausea:
- Take any anti-nausea medicines exactly as prescribed. Many people make the mistake of waiting until they are nauseous to take these medicines. Nausea is much easier to prevent than to stop once it starts. Food and nutrition can help with nausea, but medicines are your fist line of defense.
- Avoid food smells — strong odors can make nausea worse. Ask for help preparing food and stay out of the kitchen while meals are being made. Take a quick walk before each meal to get some fresh air.
- Stick to small, frequent meals. Avoid eating or drinking too much at once. Feeling overly full will make nausea more intense.
- Try low-odor, dry, and bland foods, such as crackers, toast, oatmeal, and plain yogurt.
- Sip cold, clear liquids, such as ginger ale, iced tea, sparkling water, or fruit juice. Some people find sparkling water with a splash of juice soothes the stomach.
- Sip ginger tea.
- Avoid fatty, spicy, and sugary foods.
- Suck on ginger candy or other hard candy such as mints or lemon drops. Avoid citrus flavors if you have mouth sores.
- Suck on frozen fruit such as frozen grapes, watermelon, or cherries.
- Avoid laying down immediately after meals.
- Avoid drinking large amounts of liquid with food. Instead, sip liquids slowly and often throughout the day to stay hydrated.
Probiotics generally do not help with nausea, although some people take them for diarrhea. If you want to take probiotics during chemotherapy, ask your doctor or dietitian first because they may not be safe for people with neutropenia.
Constipation and diarrhea are two other common side effects. Can you talk about how to eat for both of those conditions?
Fiber is key to managing both constipation and diarrhea. There are two types of fiber: soluble and insoluble. Soluble fiber becomes “sticky” when it gets wet. Oats, which are rich in soluble fiber, are an example of this. When you add liquid to oats, they become thick and gooey.
Insoluble fiber does not absorb much water, so it doesn’t change when liquid is added to it. Think of what a piece of celery dropped into a glass of water. It doesn’t absorb liquid or change much at all. That’s insoluble fiber.
- For constipation, include a combination of soluble and insoluble fiber in your diet. Drink plenty of liquid to help move things through your digestive tract more quickly and easily. This can ease constipation.
- For diarrhea, you want to eat ONLY soluble fiber. Think of foods that absorb water and have a sticky quality after preparation or cooking. Examples include oats, barley, and white rice.
For more soluble fiber, try:
- oats and oatmeal
- applesauce without added sugar
- very ripe pears
- finely ground flaxseeds (not whole) and chia seeds
- white rice (cook with extra water to maximize stickiness)
For more insoluble fiber, try:
- whole wheat and wheat bran
- rye-based bread and crackers
- nuts and seeds
- raw or lightly steamed vegetables
- berries and apples with the peel
Beans and peas contain significant amounts of both soluble and insoluble fiber.
A daily fiber supplement, which is mostly soluble fiber, can address diarrhea and constipation. If you aren’t currently taking a fiber supplement, ask your doctor before starting one.
Mouth sores are a problem for many people. Are there foods that are easier on a sore mouth?
The following tips can help you cope with chemotherapy-associated mouth sores:
- If you have been prescribed a mouth rinse to treat pain, time it’s use so that you can eat when your mouth is less sensitive.
- Eat your foods at room temperature or cooler.
- Avoid very hot and very cold foods.
- Avoid citrus, spicy, and strong minty flavors.
- Avoid dry and sharp foods such as toast, crackers, and chips.
- Suck on ice chips, popsicles, or frozen fruit. Some chemotherapy medications cause cold intolerance, so avoid this if you have been told to skip very cold foods.
- Avoid fruit and vegetables with small seeds.
- Do not use alcohol or tobacco.
- Avoid acidic foods and beverages such as lemons, limes, tomato sauce, oranges, and orange juice.
- Try moist, bland foods such as oatmeal, pudding, and custards.
- Avoid fizzy and carbonated beverages.
- Do not use commercial mouthwashes that contain alcohol.
- Ask your nurse if there are recommended toothpastes and other products for people with mouth sores.
If you are unable to eat due to mouth sores, tell your doctor know right away.
Many people say certain foods taste bad during chemotherapy. How can someone keep food tasty? Can you recommend some alternatives?
Altered sense of taste is a common complaint among people receiving chemotherapy. If food tastes truly terrible and you notice white patches in your mouth, tell your doctor. This can be a sign of infection in the mouth and it requires prompt treatment.
For most people, some adjustments in the types and flavors of food can help when food doesn’t taste right.
The following tips can help you cope with chemotherapy-associated changes in taste:
- If food tastes metallic, try using plastic or wooden utensils. Avoid canned fruit, sauces, and vegetables. Opt for fresh or frozen instead.
- Practice good oral hygiene. Lightly brush your tongue and gums to eliminate bad tastes.
- Ask your medical team if they recommend specific mouth rinses or toothpastes to combat odd tastes.
- Drink liquids from a “to-go” cup with a lid to minimize smells.
- Try sucking on mint or fruit flavored candies.
- Experiment with different or new spices and flavors. Try fruit sauce on meats or lemon juice and butter drizzled on vegetables or beans.
- If things taste overly sweet, add tart flavors, such as cranberry, balsamic vinegar, or lime.
- Sprinkle fresh tarragon, basil, rosemary, or thyme onto eggs, chicken, fish, or meat.
- Add frozen cranberries to fruit smoothies and cooled coffee or espresso to vanilla flavored drinks for variety.
- Eat nutrient-dense, lower-flavor foods, such as unsalted nuts and nut butters.
- Serve foods at room temperature or cooler (but make sure they are cooked thoroughly for food safety first) to lessen strong flavors.
- Try simmering potatoes and meat in broth or coconut milk.
What are the best foods for someone whose appetite is suffering because of chemotherapy?
Lack of appetite and feeling full after a few bites are common challenges for people receiving chemotherapy. If you are struggling with this issue, focus on eating good sources of protein and nutrient-dense foods.
The following tips can help you cope with chemotherapy-associated lack of appetite:
- Eat five or six small meals and snacks rather than two or three larger meals.
- Bring food with you when you leave the house. If hunger strikes, you can take advantage of it immediately. Pack granola bars, nuts, dried fruit, an apple, or a banana in your purse, bag or backpack.
- Eat by the clock. Don’t wait to feel hungry. Instead, make it a priority to have a few bites of food every hour or so.
- Avoid water, tea, coffee, diet soda, or other non-caloric beverages with meals. They can fill you up and replace the food your body truly needs.
- Include protein foods, such as eggs, nuts or nut butter, tuna, or chicken with every meal and snack.
- Add cheese to soups, stews, and casseroles.
- Enjoy custard and pudding made with whole milk for dessert.
- Drizzle olive oil over vegetables.
- Add avocado, nuts, and nut butters to salads.
Treat food like medicine. While it’s not fun to eat when you have no appetite, your body needs fuel in the form of calories and protein. Eating well can help you recover from treatment and rebuild your immune system.
Dehydration is another issue during chemotherapy. Besides drinking plenty of water, are there particular foods that can help?
Staying well hydrated is an important part of chemotherapy. Your kidneys need plenty of fluid to process and excrete the chemotherapy medicines. If you aren’t urinating regularly or your urine is a dark color, call your doctor right away.
In addition to drinking plenty of fluids, eat water-rich vegetables and fruit, such as carrots, cucumbers, celery, berries, apples, plums, pears, peaches, nectarines, and oranges.
Sip soups and broth, and enjoy smoothies made with milk or non-dairy options.
Along with these foods, minimize the risk of dehydration with the following tips:
- Carry a water bottle with you at all times. Sip from it frequently.
- Try flavored or sparkling water if plain doesn’t taste good.
- Try a squeeze of lemon or lime in your water to make it more appealing.
- Try non-caffeinated and herbal teas, such as chamomile, hibiscus, or other flavors for variety in your fluids.
- If water tastes funny, mix half water and half fruit juice for a different flavor.
- Add cucumber slices to water for a fresh taste.
There is conflicting information on the benefits of juicing, especially for people who are immunocompromised. Because there seems to be a lot of sugar in products that come from juicing, is it OK for someone on chemotherapy? Would smoothies be better since they include more fiber?
Juicing can be a great way to get more vitamins, minerals, and plant-based nutrients into your diet. Juicing should be used to add servings of fruit and vegetables to an already-healthy diet.
Before trying juicing, focus on eating five servings of whole vegetables and fruit daily. Once you meet this goal, juicing can be added into the mix.
If you are in active treatment and have lost a lot of weight, juicing may be a good option for getting valuable nutrients into your body without displacing high protein and calorie-dense foods.
You also may want to consider blending your vegetables and fruits to make healthy smoothies. Unlike juicing, blending foods into a smoothie means you get fiber.
If you do want to try juicing, the following tips will help you make the most of these beverages without overdoing it on the sugar.
- Focus on vegetables. For the healthiest juices, include more vegetables than fruits. One fruit can sweeten up your mixture, but make the other ingredients vegetables. For example, juice one carrot, a cucumber, a small beet, a piece of ginger, and a small apple.
- Drink only what you’d eat. Juice packs a lot of nutrition — and calories — in a smaller volume than whole food. For example, you need four to six large carrots to yield eight ounces of juice. You wouldn’t eat this many carrots in a sitting, so you shouldn’t drink them either.
- Drink juice with protein, and a little bit of fat. Protein and fat balance out the carbohydrates in the juice. Pair homemade juice with Greek yogurt. Sprinkle nuts and seeds into the yogurt. Or have your juice with scrambled or hard-boiled eggs, or toast and peanut butter.
- Avoid overdoing it on the same foods and nutrients. By mixing it up, you get the greatest variety of nutrients possible. You can even juice items you might throw away, such as a small broccoli stem.
- Vary how you’re consuming the same vegetables and fruit. We absorb different nutrients from the same food, depending on how it’s prepared. What you absorb from a cooked carrot is different from what you absorb from a raw carrot. Don’t rely on juicing for all of your servings of any one particular food, or you miss out on vital nutrition.
The American Cancer Society recommends eating extra protein after chemotherapy to help heal tissues and fight infection. Is there a recommended amount? What about people who are vegetarian/vegan? Can plant protein shakes work for them?
During cancer treatment, aim for at least 0.5 grams of protein per pound of body weight per day. For example, if you weigh 180 pounds, aim for at least 90 grams of protein every day.
If you have other medical issues, such as kidney or liver disease, you may need less protein. Ask your doctor or dietitian for guidance on meeting protein needs if you have chronic conditions that may affect protein needs.
Vegetarians and vegans can meet protein needs with plant foods. Plant protein shakes are one good option. These products can fill in the protein gaps for people who do not eat meat, chicken, fish, dairy or eggs. Greek yogurt and eggs are good protein sources for vegetarians. Vegans should focus on beans, lentils, chickpeas, nuts, and seeds.
Is there any amount of alcohol that is safe to drink during chemotherapy?
Chemotherapy can be taxing on the liver. Alcohol is processed by the liver. For this reason, some oncologists recommend completely avoiding alcohol during treatment.
If you have a special occasion, party, or event and want to enjoy a glass of wine, a beer, or a cocktail, check with your oncologist to make sure it’s OK.
Suzanne Dixon is a registered dietitian, epidemiologist, and medical writer.