The ESPEN guidelines on clinical nutrition in cancer provide comprehensive recommendations for the nutritional and metabolic management of patients with neoplastic diseases. Here are the key messages:

1. Nutritional Screening and Assessment: Regular evaluations of nutritional intake and body metrics from cancer diagnosis onward are crucial. Objective assessments should also include factors like nutritional intake, symptoms affecting nutrition, muscle mass, physical performance, and systemic inflammation.
2. Energy and Protein Requirements: Cancer patients should consume energy similar to healthy individuals, roughly 25-30 kcal/kg/day, and a protein intake of 1 to 1.5 g/kg/day. The guidelines emphasize the importance of adjusting nutrient intake based on the patient’s metabolic demands and not restricting energy, especially in weight-losing cancer patients.
3. Micronutrients and Supplementation: The guidelines recommend providing vitamins and minerals in amounts close to the recommended daily allowances and discourage the use of high-dose micronutrient supplements unless specific deficiencies are identified.
4. Nutrition Interventions: Nutritional interventions should increase oral intake, particularly through dietary advice, treating symptoms that impair food intake, and utilizing oral nutritional supplements when necessary. Enteral nutrition (EN) is suggested if oral intake remains inadequate, and parenteral nutrition (PN) is considered only when EN is not feasible.
5. Exercise and Physical Activity: Maintaining or increasing physical activity is recommended to support muscle mass, physical function, and metabolic pattern. This includes both aerobic and resistance exercises.
6. Specific Recommendations for Therapy Stages:
   • During Surgery: Implementing an enhanced recovery after surgery (ERAS) protocol, including pre-operative carbohydrate loading and minimizing fasting times.
   • During Radiotherapy: Nutritional support is crucial to manage side effects like mucositis and ensure adequate intake.
   • During Chemotherapy: Adequate nutritional intake and maintaining physical activity are vital, with specific adjustments based on therapy-induced side effects.
   • Post-Treatment and Cancer Survivors: Encouraging regular physical activity and a balanced diet rich in fruits, vegetables, and whole grains while maintaining a healthy weight.

7. Advanced Cancer Care: In palliative settings, the focus shifts to comfort, avoiding aggressive nutritional interventions, and emphasizing patient and family counseling on the goals of care.

The guidelines underscore the importance of integrating nutritional care throughout the cancer treatment process, tailoring interventions to individual needs, and adapting strategies based on the type and stage of treatment to optimize patient outcomes.