Why does cancer treatment require special nutritional support?

The impact of cancer treatment on the human body is comprehensive, involving not only the destruction of tumor tissue but also damage to normal cells, metabolic disorders, and fluctuations in the immune system. Especially during radiotherapy and chemotherapy, common side effects such as loss of appetite, nausea, oral ulcers, and diarrhea directly affect food intake and absorption.

At this time, nutrition is not only a basic need for "maintaining life," but also undertakes the following key tasks:

Maintaining basal metabolism and immune function: Ensuring the body has the capacity to cope with the stress of treatment and cell repair.

Preventing weight loss and muscle wasting: Cancer cachexia is a common critical condition, and early nutritional intervention can help delay it.

Improving treatment tolerance and effectiveness: Research shows that good nutritional status helps increase the completion rate of radiotherapy and chemotherapy.

Reducing the risk of infection and complications: When nutrition is insufficient, immune cell function declines, and the infection rate significantly increases.

Therefore, nutritional support is not as simple as "eating well" or "eating more," but rather involves developing a refined intervention strategy based on the type of treatment (surgery, radiotherapy, chemotherapy, immunotherapy, etc.) and individual conditions.

"Enhancing immunity" cannot rely solely on supplements

"Eating some good supplements to enhance immunity" is the first reaction of many families regarding cancer nutrition. Ginseng, cordyceps, bird's nest, shark fin, milk, stewed soup... are served at the table, bowl after bowl, hoping to drive away the disease with "high nutrition." However, there are often two major misconceptions behind this logic.

Misconception 1: Supplements = Enhanced immunity?

In fact, so-called "supplements" are often rich in fats, cholesterol, or high protein, and may not be suitable for every patient. Some traditional Chinese medicinal materials, such as cordyceps and deer antler, have immune-regulating effects in the population, but lack clinical trial evidence to support their widespread use during tumor treatment. More importantly, some "supplements" may also stimulate estrogen or interfere with drug metabolism.

Misconception 2: If you can eat, you should eat more?

Many families hold the view that "being able to eat is a blessing," but during treatment, patients have abnormal metabolic states, and excessive intake of fats and proteins may not be effectively absorbed, instead causing gastrointestinal burden. For example, some patients drink a lot of chicken soup during chemotherapy, leading to increased nausea or fatty diarrhea; some use high-calorie health products during immunotherapy, which instead triggers immune-related inflammatory responses.

The key to enhancing immunity lies not in "eating expensive or supplementary foods," but in establishing a foundation of overall nutritional balance, dietary tolerability, and avoiding food-related risks. What truly supports the immune system is sufficient high-quality protein, appropriate vitamins and minerals, antioxidant components, and a reasonable dietary rhythm.

Specific dietary requirements for different treatment methods

Cancer treatment methods are diverse, and different treatment approaches have different focuses on nutritional intake. Here are dietary adjustment ideas under common treatment methods:

Surgical treatment period

Preoperative preparation: Maintaining good nutritional status helps with postoperative recovery, and protein needs increase, so it is recommended to increase the intake of fish, eggs, and soy products.

Postoperative recovery period: If the gastrointestinal system is involved (such as gastric cancer resection or intestinal surgery), a meal separation system, small frequent meals, and soft-textured diets should be adopted, avoiding hard-to-digest and irritating foods.

Radiation therapy period

Common side effects: Oral ulcers, difficulty swallowing, decreased appetite. At this time, gentle, low-stimulation, high-energy-density foods can be used, such as steamed eggs, warm soy milk, and fine porridge.

Oral care should be conducted simultaneously: Avoid acidic and spicy foods to protect the mucosal repair environment.

Chemotherapy period

Main issues: Nausea, vomiting, taste disorders, constipation or diarrhea. It is recommended to eat light, easily digestible foods, with small frequent meals, and consume medium-temperature, non-greasy foods such as stewed soup, boiled vegetables, and mild staple foods.

Avoid "eating a lot before treatment": Many patients binge eat before treatment to "store nutrition," which instead exacerbates indigestion after chemotherapy begins.

Immunotherapy/targeted therapy period

Pay attention to immune-related reactions: such as diarrhea, elevated liver enzymes, etc., and pay special attention to liver detoxification pressure, controlling total protein intake.

Avoid interference from health products: Some plant-based active ingredients, such as ginsenosides and green tea extracts, may interfere with drug metabolism pathways.

It can be seen that dietary strategies at different treatment stages need to be "refined and layered," avoiding generalizations, and it is even more inappropriate to simplify "enhancing immunity" to "big supplements."

Basic principles and suggestions for ingredient selection

Diet during the treatment period emphasizes "nutritional density" rather than "exotic foods." The following principles help build a suitable ingredient structure for the cancer-fighting period:

High-quality protein

Recommended sources of easily digestible protein include fish, eggs, poultry, and tofu, while avoiding fried red meat and processed meat products. Eggs (especially the yolk) are rich in choline, which helps with liver metabolism and repair.

Examples of consumption: steamed egg custard, salmon porridge, steamed chicken breast, scallion tofu soup.

Low-fat, high-fiber vegetables

Leafy vegetables provide folic acid, antioxidants, and dietary fiber, but cooking methods should be adjusted according to gastrointestinal tolerance, preferably steaming, boiling, and using little oil without adding spicy seasonings.

Examples of consumption: steamed spinach, stir-fried broccoli, pumpkin porridge, carrot stewed ribs.

Complex carbohydrates and whole grains

Avoid refined sugars and high-GI staple foods (such as white bread, desserts), using brown rice, millet, and quinoa as a base to ensure stable energy release.

Examples of consumption: brown rice, millet yam porridge, red bean quinoa rice.

Moderate fruits

Choose low-sugar, high-antioxidant fruits, such as blueberries, grapefruit, and apples. Avoid juices and canned fruits due to high sugar concentration.

Examples of consumption: apple puree, diced kiwi, cold dragon fruit salad.

Control oil, salt, and sugar

Excessive seasonings not only increase the burden on the kidneys and liver but also affect appetite and digestive function. Cooking should primarily focus on steaming, stewing, and boiling.

Case analysis: Eating right is more important than eating a lot

Case 1: Aunt Lin, post-lung cancer surgery during radiation therapy

Aunt Lin is nearly 60 years old and has a slim build. After surgery, her family insisted on "stewing soup every day," even serving bird's nest and shark fin. However, soon after, she began to experience bloating and loss of appetite, with elevated liver enzymes. The doctor suggested stopping the "supplement soup" and switching to small frequent meals with warm liquid foods, such as steamed egg custard, pumpkin porridge, and warm soy milk. After a month, her physical strength gradually recovered, and her weight stabilized with a slight increase.

Case 2: Mr. Liu, during targeted therapy for liver cancer

Due to side effects causing dry mouth, bitter taste, and severe constipation, Mr. Liu tried to self-regulate with honey, goji berries, and medicinal wine, resulting in severe fluctuations in liver function. After a nutritionist intervened, his dietary structure was rearranged, eliminating all unnecessary health products and medicinal dishes, and selecting soft, easily digestible ingredients such as pumpkin, lotus root powder, tremella soup, and tofu. His liver function indicators gradually recovered, and the treatment course was able to continue.

These two cases clearly demonstrate that during treatment, "eating right" is far more important than "eating a lot." "Food supplementation" is not about stacking supplements but rather about scientific intervention based on understanding the body's condition.

The role of family members: Scientific care rather than emotional feeding

In cancer treatment, family members often feel more anxious and express love and support through "eating more" and "supplementing." However, this emotional feeding can easily overlook the patient's appetite, digestive capacity, and clinical realities.

The positive roles that family members can play include:

Assisting nutritionists in developing personalized dietary plans

Paying attention to ingredient safety and hygiene to avoid cross-infection

Understanding the patient's appetite fluctuations and avoiding forced feeding

Creating a good dining atmosphere to alleviate the patient's resistance

Recording daily intake, weight changes, digestive status, and other data to facilitate the medical team's assessment of intervention effects

Cancer treatment is not a solitary battle, and dietary intervention is not a short-term strategy. In this process, the collaboration of patients, family members, professional nutritionists, and doctors is a key link to improve treatment outcomes, reduce complications, and extend the quality of life.