diet and nutrition Build a foundation for good health and longevity. Our diet plays a dual role when it comes to health and disease: a balanced diet protects health and reduces the risk of non-communicable diseases, while a consistent nutrient-rich diet supports healing, recovery and maintains energy levels during cancer treatment.
Role of diet in oncology
For individuals undergoing cancer treatment, nutrition becomes more than a matter of general well-being—it becomes an important component of treatmentCancer and its treatments place extreme stress on the body, resulting in greater needs for energy, proteins, vitamins and minerals, Adequate nutritional intake aids tissue repair, maintains immune function, maintains a healthy body weight, and increases the body’s ability to tolerate and recover from medical treatments, When these needs are not met, patients are at greater risk of malnutrition and cancer cachexia, a serious condition marked by involuntary weight loss, muscle wasting, weakness, and decreased physical ability,
Furthermore, cancer-related fatigue is a common, distressing symptom experienced by patients. This fatigue often persists despite rest or sleep. Nutrient-rich foods help stabilize energy levels by reducing inflammation, preserving muscle and maintaining metabolic balance. Thus, nutrition plays both a supportive and therapeutic role – helping patients cope with both the physical stress and emotional challenges associated with cancer and its treatment.
Nutritional Challenges
Surgery, radiation, and chemotherapy can create substantial nutritional challenges. While they increase the body’s energy and protein needs, they also often cause side effects that result in reduced food intake.
Radiation therapy can affect healthy tissues surrounding the tumor, especially in the head, neck, abdomen, or pelvic areas. Side-effects may include fatigue, loss of appetite, mouth ulcers, difficulty swallowing, diarrhea, constipation, and progressive weight or muscle loss.
Chemotherapy increases the nutritional requirements of the body. However, side effects such as nausea, vomiting, mouth ulcers, taste changes, diarrhea, constipation, and fatigue often make it challenging to consume adequate food and patients may require other types of feeding (tube, enteral, or parenteral nutrition).
surgical treatment Increased nutritional demands during the healing process. Depending on the surgery, patients may initially require a liquid diet, texture-modified foods, or small frequent meals. Some patients may require enteral feeding: Enteral or tube feeding is a method of delivering liquid nutrition directly into the stomach through a tube when a person is unable to eat or swallow safely by mouth, or parenteral (intravenous) feeding.
therapeutic diet
Cancer care recognizes diet as an important part of the treatment process. The therapeutic diet is designed to maintain nutritional status, support metabolic function, resolve disease-related symptoms, minimize treatment side effects, and accelerate overall recovery. These diets are planned by trained dietitians in collaboration with oncologists and tailored to meet the specific needs of each patient.
Two important therapeutic regimens frequently used in oncology include:
High-protein diet: While recovering from chemotherapy, radiation, or surgery, the body needs more protein to repair tissues, maintain muscle strength, and support immune function. The high-protein diet helps prevent muscle loss, promotes wound healing and increases patients’ flexibility during treatment.
Neutropenic Diet:Patients with low white blood cell counts, usually due to chemotherapy-induced neutropenia, are at increased risk of infection. The neutropenic diet emphasizes hygienically prepared, well-cooked foods that minimize exposure to harmful microorganisms.
early nutritional intervention
Early identification of nutritional risks and timely dietary intervention can significantly improve outcomes. Ideally, nutritional screening should begin at the time of diagnosis and the patient should be optimized before treatment begins (pre-habilitation).
Nutritional care should always be individualized. Factors such as type of cancer, treatment methods, stage of the disease, side effects, and cultural food preferences must be considered. Dietitians play an important role in providing evidence-based guidance by following established nutrition protocols such as those of the European Society for Clinical Nutrition and Metabolism and the Indian Association for Parenteral and Enteral Nutrition.
During treatment, patients should consume culturally familiar, easily digestible foods; Eat small, frequent meals; Maintain adequate hydration; Increase protein intake to support muscles; Follow a balanced diet to meet nutrient and fiber needs; And ensure strict food safety, especially if immunity is weak.
Daily diet dictates health
Diet, nutrition and lifestyle changes are companions to good health throughout life. We live in a world that is filled with fast food, sugary beverages. processed foods And unhealthy snack choices. These, coupled with a decrease in nutritious home-cooked food, have tipped the balance towards an increase noncommunicable diseasesTherefore, it is imperative to increase our knowledge about the role of diet on our health,
Several scientific reviews note that Mediterranean type diet Reduces the risk of cancer (by reducing oxidative stress, preserving cellular health and reducing the incidence of obesity) through high intake of fiber, antioxidants and healthy fats (mono-unsaturated fats: polyphenol and oleocanthal sources through olive oil, and nuts and omega fatty acids through fish). The mechanism of action is the reduction of oxidative DNA damage which is the central driver of carcinogenesis. Additionally, many Indian spices (such as turmeric, ginger, cumin and coriander) are rich in bioactive compounds (including curcumin and gingerols) that exhibit Anti-inflammatory and antioxidant properties and are also known to modulate key signaling pathways. Conversely, a diet rich in processed meats, refined grains and added sugars lacking fiber-rich foods may increase cancer risk.
When choosing extra servings, choose vegetables, fruits, whole grains, pulses, nuts and seeds that unlock the protective power of fiber, vitamins and minerals. These foods support a healthy gut microbiome, strengthen immunity, reduce inflammation and support healthy body weight, thereby reducing the risk of obesity-related cancers (breast, colorectal, endometrial, kidney and pancreatic cancers).
In short, for one Healthy Diet and Lifestyle: Increase your intake of whole grains, vegetables, fruits, pulses, beans, nuts and seeds; Reduce fast food, red and processed meat; Limit sugar-sweetened beverages and alcohol; Quit tobacco; Maintain a healthy body weight and remain physically active consistently.
Dietary guidance for patients during treatment
| Choose culturally familiar foods: | Diets based on rice, millet, pulses, vegetables and fermented foods are nutritious and easy to digest. |
| Eat small, frequent meals: | When appetite is low, eating smaller meals more frequently helps maintain energy levels without putting pressure on the digestive system. |
| Stay well hydrated: | Patients should drink at least two liters of fluids daily unless medically prohibited. |
| Increase protein intake: | Protein-rich foods – such as cheese, eggs, lentils, milk, curd, nuts and lean meat – help preserve muscle. |
| Maintain balanced nutrition: | Including whole grains, fruits, vegetables, healthy fats and proteins ensures that the body gets vitamins, minerals, fiber. |
| Prioritize food safety: | Immunocompromised patients (low white blood cell counts) need to adopt strict hygiene measures. |
Looking ahead, for both our health and the planet EAT-Lancet Commission propose a “universal healthy reference diet” that largely plant basedEnvironmentally sustainable and capable of preventing diet-related non-communicable diseases.
Every morsel we eat is our first medicine: the choice of good health can be made within the confines of our kitchen, and the time to make this choice is now.
(Dr. Rama R. is Associate Professor and Head, Department of Epidemiology, Cancer Institute (WIA). r.rama@cancerinstitutewia.org; Dr. Parvati K. is Dietician, Department of Dietetics, Cancer Institute (WIA) diet@cancerinstitutewia.org; Dr. Mahalakshmi Rangabashyam Shetty is Consultant, The Head and Neck Clinic and Practice Professor, Department of Medical Sciences and Technology, Indian Institute of Technology, Madras. mranagabashyams@iitm.ac.in)
