Cancer And Nutrition: What To Eat When Dealing With These 10 Treatment Side Effects

Cancer And Nutrition: What To Eat When Dealing With These 10 Treatment Side Effects

Nutrition is a key element in every cancer-patient's disease-fighting strategy. Each person's ideal nutrition will of course vary based on treatment and cancer type, but eating well can help you maintain your strength, build up your body's store of nutrients, lower infection risk, and heal faster.

Your care team can talk to you about what specific nutrients you should focus on based on your treatment plan, but getting enough calories may be a bigger concern than where your calories are coming from. Cancer patients often need extra calories and protein to maintain their weight and strength.

The challenge is that cancer treatments offer an array of side effects that make it difficult to eat healthy—or to eat at all. Below is a list of 10 of the more common cancer treatment side-effects and how to eat well while dealing with them. Be sure to let us know if you have any tips to add!

How to eat when you are experiencing...


10. Nausea/vomiting

If you experience nausea and/or vomiting, be sure to tell your care team as there are some medications that can help.

Also try:

  • Eating small meals or snacks throughout the day instead of large meals
  • Avoiding strong odors both in your food and in your environment. Eat where there is fresh air and avoid warm, stuffy rooms.
  • Eating dry foods like toast, cereal, and crackers.
  • Going for bland, soft foods like oatmeal and soup, and avoid spicy and strongly flavored foods.
  • If you're vomiting, dehydration can be a concern. Take small sips of water or other liquids throughout the day to stay hydrated.
  • After meals, try rest sitting up rather than lying down.
  • Go ahead and eat the foods that do appeal to you, and worry less about eating the "right" foods.

9. Diarrhea

Diarrhea is vomiting's ugly twin. It's frustrating, exhausting, and often embarrassing. But remember, your treatment team is used to these side effects, and they want you to feel the best that you possibly can. Be sure to tell your care team if you have diarrhea for more than 24 hours or if your stools have an unusual smell or color.

You should also:

  • Drink plenty of clear liquids with mild tastes like water and sports drinks. Diarrhea can put you at risk of dehydration, so keep drinking small sips throughout the day.
  • Avoid strongly flavored foods. More bland, neutral foods are the way to go.
  • Limit dairy products unless they are low-lactose or lactose-free.
  • Avoid gas-causing foods like gum, carbonated drinks, raw fruits and vegetables, and beans.
  • Avoid alcohol and foods made with sugar alcohol.
  • Avoid or reduce caffeine.

8. Constipation

Perhaps you are lucky enough to avoid diarrhea, but medications, nutrition changes, and being less active can cause problems at the opposite end of the spectrum: constipation. Constipation can cause gas, bloating, and stomach cramps. Aren't there ever any good side effects?

Here are some strategies to try:

  • Eat high-fiber foods, but only after getting the go-ahead from your care team, as these are sometimes not recommended for cancer patients.
  • Try to consume 8 to 10 cups of liquid a day.
  • While you're at it, try warm beverages, as these can help prompt a bowel movement.
  • Try to be as active as possible. Activity can help keep you regular.
  • Talk to your doctor if you haven't had a bowel movement in 2 or more days. No need to be embarrassed—just say, "Doctor, I'm really backed up down south!"

7. Loss of appetite

Exhaustion, nausea, frustration, and even depression may make eating anything seem like a giant chore. Calories are important to keep your strength up, so try some of these tips:

  • Go for small snacks throughout the day instead of big meals.
  • Eat whatever appeals to you. Don't waste time worrying about what you should be eating for optimal health. If there's something that sounds good and hasn't been prohibited by your doctor, go for it!
  • Stock your fridge, pantry, purse, car, and pockets with high-calorie, high-protein foods. When you do feel like eating, you'll have something on hand.
  • If you can, try exercise. Exercise builds up your appetite.
  • Ramp up your liquid calories. Try a meal replacement drink and juices or milk over water. Every calorie counts!
  • But try to not drink too much during meals. Drinking can help you to feel full quicker, so focus on solid food first when eating.

6. Sore throat/mouth

Cancer treatments like radiation, chemotherapy, and immunotherapy can cause mouth sores, a sore mouth, or a sore throat. This discomfort will most likely end when your treatment ends.

Until then, try:

  • Eating soft, bland foods and avoiding crunchy, spicy, and acidic foods. Overly salty and tomato-based foods can also cause trouble.
  • Eating cool or room temperature foods instead of hot foods. This is your green light to enjoy lots of frozen yogurt and smoothies!
  • Avoiding mouthwashes that contain alcohol.
  • Avoiding alcohol, caffeine, and tobacco.
  • Softening hard foods. Add milk or water, or try dipping foods in sauce.
  • Talking to your doctor about numbing mouthwash and if it might be a good option for you.

5. Dry mouth

Cancer treatment can damage the glands that make saliva. This can cause dry mouth and change the way food tastes. Check out this dental hygienist's tips for dealing with chemo and dry mouth.

Also try these strategies:

  • Sip water through the day. Try using a straw if your throat is sore.
  • If you don't have a sore mouth or throat, try very sour or very sweet foods, as these can stimulate saliva production.
  • Avoid mouthwash unless you make it yourself using water, salt and baking soda (see the American Cancer Society's mouth rinse recipe here).
  • Try candy or gum to keep your mouth moist. Sugar-free is best unless you have diarrhea, as sugar-free candy can exacerbate diarrhea.
  • Avoid alcohol, tobacco (including second-hand smoke) and caffeine.
  • Talk to your dentist about products that can help keep your mouth moist and clean.

4. Weight Loss

Please, cancer treatment is not to be thought of as a diet strategy. Maintaining a healthy weight is hugely important when it comes to reducing your risk of recurrence, but during treatment, you need plenty of calories to help you endure treatment and fight cancer cells. Some weight loss may be unavoidable, but it should not be embraced.

Try these tips to keep up your weight:

  • Go for high-calorie foods. In life you will rarely receive this advice, so take advantage of it! Try adding high-protein and high-calorie foods to other foods by adding sauces, toppings, and spreads.
  • If you are dealing with loss of appetite, it may be best to eat on a schedule that your body can get used to rather than wait until you are hungry. Try smaller, more frequent meals if those are more palatable.
  • Drink milkshakes and smoothies—preferably ones that include plenty of protein.

3. Weight Gain

Treatment may cause weight loss, but some treatments may cause weight gain instead. Women going through breast cancer treatment are more likely to gain weight. Oh for heaven's sake!

Try to keep a positive mental attitude. Those extra pounds put you at your fighting weight! Still, here are some strategies to help you avoid gaining too much weight:

  • Talk to a dietitian (talk to your care team for a referral) about the best ways to get the nutrition you need without gaining weight.
  • Stay active, and try to choose activities that both burn extra calories and relieve stress. Reducing stress can help reduce stress-related snacking. Even small, easy bouts of exercise can be helpful.
  • Good, basic nutrition tips are your friends here: limit salt and fat, go for lots of vegetables and high-fiber foods, and limit sugar intake.

2. Fatigue

This is a big one, and probably all cancer patients deal with some fatigue caused by stress, chemotherapy, medication, a busy treatment schedule, or all of the above. Try these strategies to combat fatigue:

  • Stay hydrated as dehydration can make fatigue worse.
  • Go for a mix of protein, fiber, and fat with each meal to help stabilize your blood sugar.
  • Do not try to fix your fatigue with supplements unless they are recommended by your treatment team. Supplements are not regulated by the FDA.
  • Take lots of naps and let others help you with chores and errands! This is not food-related advice—it's just good advice!

1. Avoid Foodborne Illness

OK, this is not really a side-effect of cancer treatment. But it's certainly worth mentioning. When you are dealing with a weakened immune system and trying to fight off cancer, the last thing you want to do is deal with an infection or illness that could have been avoided. Be vigilant about your usual safety precautions when preparing and handling food.

Also keep these tips in mind:

  • Be temperature savvy. Keep your hot foods hot and cold foods cold, and put leftovers in the refrigerator right away after eating.
  • Be meat savvy. Make sure that your hands, utensils, and cooking surfaces are clean before preparing meat, and clean all surfaces afterwards. Always wash your hands after each time you touch raw meat, and use a separate cutting board for meat and for other food. Thaw meat in the fridge or microwave, not the countertop, and don't refreeze after thawing. And of course, cook all meats thoroughly!
  • Thoroughly wash all fruits and vegetables with water and a vegetable scrubber. Soak fruits or veggies that are difficult to scrub. You should even wash produce with a rind or peel before cutting or peeling.
  • Avoid foods with mold, including moldy cheeses.
  • Look out for any situations where other hands have come into contact with food before yours. This includes buffets, bulk bins, condiment bottles that stay on tables at restaurants, and salad bars. It's OK to be picky while you're going through treatment!
  • Stay away from raw nuts, raw fish or shellfish, and undercooked meats and eggs. Err on the side of caution!
  • Wash your hands well before eating, after eating, and basically, any time you feel like you have come into contact with germs. Use soap and warm water and wash for twenty seconds.

Well, that's our list! We hope you found some of these tips helpful. Remember that your medical care team and dietitians will be excellent sources of personalized information, so talk to them early and often. Each person is unique, and no one thing will work for every person. Be patient, gather support, and take things one step at a time. Keep fighting, friends!

Katie Taylor

Katie Taylor started writing in 5th grade and hasn't stopped since. Her favorite place to pen a phrase is in front of her fireplace with a cup of tea, but she's been known to write in parking lots on the backs of old receipts if necessary. She and her husband live cozily in the Pacific Northwest enjoying rainy days and Netflix.

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