“Cancer care has undergone a profound transformation over the past few decades. Advances in early detection, targeted therapies, immunotherapy, and supportive care have extended survival and reshaped cancer into a condition that, for many, is managed over years rather than months. Within this evolving landscape, nutrition has moved from the margins of oncology to a position of growing clinical relevance, spanning prevention, active treatment, and long-term survivorship.
Cancer is not always a purely localized process; many cancers and many cancer treatments have systemic effects that disrupt metabolism, immunity, and functional capacity. Tumor-induced inflammation, altered energy expenditure, hormonal changes, and treatment-related toxicities can all impair nutritional status. These effects may occur at any stage of disease, not only in metastatic settings, underscoring why nutrition deserves attention from diagnosis onward.
From a prevention perspective, the role of diet is now well established at the population level. Dietary patterns characterized by high intake of fruits, vegetables, whole grains, and dietary fiber, alongside limited consumption of processed and red meats, alcohol, and energy-dense ultra-processed foods, are consistently associated with reduced risk of several common cancers.
Nutrition intersects here with other modifiable lifestyle factors, such as physical activity and body weight regulation, forming the foundation of primary cancer prevention strategies. While nutrition alone cannot eliminate cancer risk, it meaningfully shapes the biological environment in which carcinogenesis occurs, influencing inflammation, insulin resistance, oxidative stress, and the gut microbiome.
During active cancer treatment, nutritional challenges become more acute. Treatment-related side effects such as nausea, mucositis, taste alterations, dysphagia, diarrhea, and fatigue often compromise dietary intake. At the same time, systemic inflammation and metabolic alterations may increase nutrient requirements or accelerate muscle loss. Malnutrition is common, particularly in advanced disease and in tumors affecting the gastrointestinal tract or swallowing, such as head and neck or upper gastrointestinal cancers. Importantly, malnutrition in oncology is not limited to low body weight; it may coexist with overweight or obesity and is frequently driven by loss of lean body mass and functional decline.
Evidence consistently shows that better nutritional status is associated with improved treatment tolerance and fewer interruptions, whereas malnutrition is associated with higher toxicity, postoperative complications, infections, and prolonged hospital stays. These associations highlight nutrition as a key component of supportive care rather than a peripheral concern. Nutritional assessment and timely intervention can help preserve functional capacity, support adherence to treatment protocols, and reduce the risk of unplanned dose reductions or delays. However, it is equally important to frame these findings carefully: improved nutritional status is associated with better outcomes, but nutrition is one element within a complex network of clinical, biological, and social determinants of health.
As survival improves, attention is increasingly shifting toward survivorship. Millions of people worldwide now live with a history of cancer, facing long-term and late effects of disease and treatment, including fatigue, sarcopenia, cardiometabolic risk, bone loss, and psychosocial challenges. Nutrition plays a central role in addressing these issues. Post-treatment dietary guidance focuses not only on recurrence risk reduction but also on restoring metabolic health, maintaining muscle mass, supporting cardiovascular health, and improving quality of life. For survivors, nutrition is closely intertwined with physical activity and behavioral support, emphasizing sustainable dietary patterns rather than restrictive or unproven regimens.
Despite growing evidence, nutrition remains inconsistently integrated into routine oncology care. Screening for nutritional risk is not universally implemented, access to trained oncology dietitians is uneven, and nutrition is often addressed reactively rather than proactively. This gap reflects broader structural challenges, including limited time, resources, and historically sparse representation of nutrition in oncology guidelines. Nevertheless, integrating nutrition into standard oncology care is increasingly recommended to support treatment tolerance, functional outcomes, and quality of life across the cancer continuum.
Looking forward, the role of nutrition in cancer is likely to become more personalized and evidence-informed. Emerging research on metabolic phenotyping, body composition analysis, and the microbiome is refining our understanding of how individuals respond to both disease and therapy. At the same time, implementation science is needed to translate nutritional evidence into practical, equitable models of care.
From prevention to survivorship, nutrition is not a standalone cure, nor is it a substitute for medical treatment. It is, however, a powerful modifier of risk, resilience, and recovery. Recognizing and embedding nutrition as a core component of comprehensive cancer care represents an essential step toward more holistic, patient-centered oncology.”
Written by Raisa Mehzabeen
BSc. (Honors), Food and Nutrition, DU
MPH ( Running), Public Health Nutrition, North South University
PGT on Nutrition and Fitness Training, Inspiron Fitness and Diet Consultancy Centre
Chief Executive Officer, Nutrition For Change
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