Nutrition during cancer: Doctor busts food myths with medical facts

By Admin

06 Feb, 2026

As cancer care becomes more personalised, nutrition must follow the same path. Fear-driven food rules and viral diet trends often overwhelm patients at a time when clarity and strength matter most. The core message from experts is simple yet powerful: adequate nourishment supports recovery, while unnecessary restriction can do harm.

In an exclusive interaction, Veena V, Chief Clinical Dietician and Head of the Department of Clinical Nutrition and Dietetics at Aster Whitefield Hospital, Bengaluru, cuts through popular myths with evidence-based guidance. Drawing from years of clinical experience, she explains why nutrition is not an optional add-on but a central pillar of cancer treatment.

There is no single food that cures or feeds cancer

One of the most persistent beliefs in cancer care is that certain foods can either cure cancer or make it grow faster. According to Ms. Veena V, this is a dangerous oversimplification.

“There is no one food that can either cure cancer or make it grow,” she explains. What truly matters is maintaining good nutritional status so patients can tolerate treatment, heal effectively, and maintain a better quality of life.

The appeal of food myths is understandable. Diet feels like something patients can control during an uncertain illness. However, cancer biology does not operate in absolutes. Cancer metabolism is complex, and reducing it to a single nutrient ignores decades of scientific research.

Weight loss is not normal, it is a warning sign

Unintended weight loss is often dismissed as an inevitable part of cancer, but medically, it is a red flag.

“Many cancer patients experience weight loss or reduced ability to eat, and this can directly impact treatment response and recovery,” says Ms. Veena V. She stresses that nutrition intervention should begin at the very start of treatment, not after complications arise.

Clinical evidence shows that malnutrition increases treatment toxicity, delays wound healing, weakens immunity, and can even reduce survival. Early and proactive nutrition planning helps preserve muscle mass, functional strength, and the ability to continue therapy without interruptions.

The sugar myth and why cutting sweets will not starve cancer

Among all food myths, the idea that sugar feeds cancer is perhaps the most widespread.

“Yes, cancer cells use glucose,” Ms. Veena V clarifies, “but so do all healthy cells in your body. Avoiding sugar will not cure cancer, and eating sugar does not suddenly make cancer worse.”

She cautions against extreme calorie restriction, especially very low-calorie diets.

“Diets under 800 calories can significantly weaken patients and interfere with treatment response,” she warns.

The real focus should be on calorie adequacy, weight stability, and overall metabolic health, not fear-based elimination of specific foods.

Protein and calories are the real allies during treatment

If there is one clear nutritional priority during cancer care, it is meeting energy and protein needs.

“Protein and calories are your friends during treatment,” Ms. Veena V says. They help maintain muscle, support tissue repair, and improve tolerance to chemotherapy or radiation.

Many patients struggle with poor appetite, nausea, taste changes, or fatigue. In such cases, oral nutritional supplements play an important role.

“These supplements are not a failure,” she explains. “They are a medical necessity when food alone is not enough.”

For patients with severe cancer-related weight loss or cachexia, she emphasises a multidisciplinary approach that combines nutrition therapy, medications, and appropriate physical activity for the best outcomes.

Lifestyle choices that truly make a difference

While extreme diets dominate social media, evidence-based lifestyle habits remain far more effective and safer.

Ms. Veena V recommends a balanced diet that includes plant-based foods, staying physically active within individual limits, and avoiding heavy alcohol consumption. These choices support immune function, heart health, and long-term survivorship without exposing patients to unnecessary nutritional risks.

Her most practical advice is also the most important.

“If you or a loved one is undergoing cancer treatment, ask your oncology team for a referral to a dietitian,” she says. A personalised nutrition plan, designed around the patient’s treatment and symptoms, is far more valuable than any internet trend.

In cancer care, strength comes from nourishment, not restriction. Trusting medical evidence over fear-based myths can make a meaningful difference in treatment tolerance, recovery, and quality of life.