Dietary Guidelines During Cancer Treatment and How to Deal with Common Side Effects

Cancer treatment may cause many side effects. As cancer treatment is personalized for each patient, the occurrence and severity of side effects may vary from person to person.

The common side effects experienced by patients with cancer include

Nausea or vomiting

Nausea and vomiting may occur after chemotherapy and radiation therapy to the head, abdomen, and pelvis. Not all patients face these issues, and for those who do, the severity can vary. Patients can ask their doctors for anti-nausea medications to alleviate these symptoms. Additionally, dietary recommendations include:

Increasing nutrient intake through frequent, small meals. This not only reduces the burden on the stomach but also aids digestion and reduces the feeling of nausea.
Eating more when appetite is at its best (usually during breakfast). Choose bland, easily digestible foods like congee, oatmeal, noodles, and smoothies.
Foods with a salty or sour taste, such as pickled plums, ginger candies, and mint candies, can help reduce nausea.
Hot foods can produce smells that may induce nausea. Opt for cold or room temperature foods.
Try to avoid greasy, spicy, and heavily flavored foods to prevent stomach irritation and the onset of nausea and vomiting.
Drink water or other beverages at regular intervals and in small amounts, such as barley water, herbal tea, chrysanthemum tea, ginger tea, clear soup, smoothies, etc., to avoid dehydration.
You can try adding ginger to your dishes, as it can help relieve nausea.

Mouth and Throat Pain

Some chemotherapy and head and neck radiation therapy can cause mouth and throat pain. Radiation can lead to damage and inflammation of the oral mucosa, causing pain and discomfort. Therefore, maintaining good oral hygiene and keeping the mouth moist is crucial. Dietary recommendations include:

Choosing foods that are moist, soft, and easy to chew, such as mushroom soup, congee, rice porridge, pudding, mashed potatoes, scrambled eggs, etc.
Consume 8 to 10 cups of fluids a day, primarily plain water, but herbal teas like chrysanthemum tea, winter melon tea, and other cooling drinks can help keep the throat from getting too dry.
If swallowing is an issue, cut food into small pieces or cook until it's soft. You can use a blender to make it into a puree.
Avoid foods that can irritate the mouth, such as

Very spicy, sour or salty foods. For example, curry, chili, orange, orange juice, pineapple, asparagus, Thai hot and sour soup, pepper, pickled fruits and vegetables.
Drinks that contain caffeine or high sugar content to avoid drying out your mouth.
Very hot or very cold food and drinks. High or low temperatures can further irritate your mouth. Warm food should be consumed.
Hard, crunchy and rough foods such as lettuce and fruit, nuts, crackers, crackers and whole wheat bread.
Fried and grilled foods, as these foods are generally harder. Try steaming, stewing or slow-cooking your food to make it softer and more tender.
Carbonated and alcoholic drinks

Taste Changes

Many patients may experience a bitter or metallic taste in their mouths during cancer treatment. Some patients may not be able to taste food, leading to a decreased appetite. These taste changes are usually temporary and gradually disappear after treatment. Dietary recommendations include:

Using seasonings and spices when cooking, such as five-spice powder, cinnamon, basil, rosemary, ginger powder, lemon juice, and tamarind, to enhance the flavor of food and stimulate appetite.
Try pairing meat with other foods like chili, pasta sauce, or broth. Meat can also be marinated in sauces, juices, or wine to remove any strong flavors and improve the taste of the food.
Use honey or dried fruits like raisins, figs, dates, etc., to increase sweetness.
Brush your teeth and rinse your mouth before meals.
Use ceramic or silicone tableware instead of metal utensils to reduce the metallic or bitter taste in your mouth.
Chew on sour plums, sugar-free lemon candies, gum, or mint candies after meals to eliminate any lingering bitter or metallic tastes.
Certain food odors may trigger aversion or nausea. Try to temporarily avoid contact with these foods, such as fishy odors.

Changes in Appetite

During the course of cancer treatment, patients may experience fluctuations in their appetite, with moments of craving for food and periods of food aversion. These fluctuations can have a significant impact on their energy and nutrient intake. Consequently, it is advisable for patients to seize moments of heightened appetite to incorporate calorie-rich, protein-packed, and nutrient-dense foods into their diet. Recommendations include:

Eating small, frequent meals. There's no need to restrict food portions, and there's no pressure to finish everything. Don't force yourself to eat foods you don't like or have no appetite for.
Eating at regular intervals. Have small snacks every 2 to 4 hours to supplement energy.
Options for snacks include dried fruits, pancakes, dim sum, sandwiches, fruits, yogurt, smoothies, jelly, pudding, biscuits, nuts, seeds, etc.
Try new foods to stimulate your appetite.
Maintain a regular exercise routine to increase appetite.
If there's no appetite, consider using appropriate oral nutritional supplements.

Diarrhea

Diarrhea may be caused by abdominal radiation, chemotherapy, dietary changes, or other medications.

When diarrhea is severe, a low-fiber diet can help the intestines rest.
It's important to stay hydrated and replace electrolytes to prevent dehydration. Potatoes and bananas are high-potassium foods that can help replenish lost electrolytes during diarrhea.
Avoid consuming irritating foods like spicy foods, caffeine, and fried foods, as they can worsen diarrhea.
Try soft, bland, and low-fat foods such as congee, clear meat broth, rice noodle soup, steamed eggs, etc., which are easier for the body to absorb and digest.
Temporary lactose intolerance may develop due to diarrhea. If this occurs, try lactose-free or low-lactose milk.
Increase the intake of soluble fiber foods, as soluble fiber can absorb water and form a viscous substance in the stool. Examples include spinach, kale, broccoli, oatmeal, oat porridge, and oat bread. You can also add red beans, mung beans, and black beans to soups or desserts.
Once diarrhea stops and your condition improves, you can gradually return to a balanced diet.

Constipation

Cancer treatment or certain medications can lead to constipation or difficulty passing stool.

Increasing dietary fiber intake helps soften the stool and promotes intestinal motility. When planning your menu, include at least one high-fiber food per meal, such as fruits and vegetables, whole grains, and legumes.
Consume enough fluids, at least 8 to 10 cups, including soups, milk, smoothies, etc. Plum juice contains sorbitol, which can help with bowel movements and alleviate constipation, consuming about half a cup a day is recommended.
Establish regular meal times and cultivate good bowel habits.
Engage in light exercise, such as walking or climbing stairs slowly, to stimulate bowel movements and promote regular bowel movements.

Weight Loss

Cancer treatment or inadequate daily nutrition can lead to weight loss. Therefore, you need to increase the nutritional density of foods and beverages to meet the patient’s protein and calorie requirements to avoid muscle loss. Additionally, it is important to have adequate energy to cope with the side effects of cancer treatment. Recommendations include:

Add minced meat, fish, eggs, tofu, pumpkin, sweet potatoes, or sesame oil to porridge.
Include avocado, chia seeds, or flax seeds in your smoothies.
Add eggs, tofu, or lean meat to your soup.
Mix nut butter, dried fruits, plain yogurt, or nuts into your oatmeal.
Include cheese, nut butter, or eggs in your sandwiches.
Use olive oil, sesame oil, or coconut oil to enhance the calorie content of your food.

If the patient continues to lose weight without improvement, consult a dietitian immediately.

During cancer treatment, patients may often feel discouraged, depressed, and worried about various side effects that can affect their nutritional needs. Therefore, the encouragement and understanding of family and friends are crucial. Patients and their families should not believe in unscientific rumors or extreme diets that could delay the golden period of treatment. They should actively cooperate with professional doctors, dietitians, and other healthcare personnel because they have the most specialized knowledge and experience to provide the most accurate diagnosis, treatment, and nutritional advice, to help patients fight cancer successfully to the greatest extent. Family and friends can also play a vital role in supporting cancer patients by helping them maintain a healthy and balanced diet. Simple and nourishing meals, such as a delicious porridge recipe for cancer patients, can help ensure that patients are getting the nutrients they need to support their treatment. By working closely with healthcare professionals and providing a supportive environment, loved ones can help cancer patients feel more optimistic and resilient as they navigate their journey towards recovery.