The Efficacy and Safety of Nutritional Supplements for Cancer Supportive Care: An Umbrella Review and Hierarchical Evidence Synthesis.

This comprehensive review examined whether nutritional supplements can help cancer patients manage treatment side effects. Researchers analyzed 52 reviews covering 250 randomized controlled trials that tested 18 different supplements for 16 cancer-related conditions. The study excluded supplements for pain, anxiety, and depression, focusing instead on other common challenges like radiation burns, chemotherapy-induced nerve damage, and mouth sores. The researchers found moderate-quality evidence that certain amino acids and oral proteolytic enzymes may help reduce the severity of radiation-induced skin reactions. N-acetyl cysteine showed promise in preventing nerve damage from chemotherapy in people with gastrointestinal cancers. Several other supplements showed potential benefits but with lower-quality evidence: glutamine, zinc, probiotics, and melatonin may help with mouth sores; vitamin E, omega-3 fatty acids, glutamine, and other amino acids may prevent chemotherapy-related nerve damage. While most supplements were safe with only minor side effects, high-dose vitamin A caused serious adverse events, and zinc and vitamin E had dose-related problems. However, the majority of evidence was low to very low quality, meaning these findings are uncertain. The researchers concluded that while some supplements show promise for managing cancer treatment side effects, more rigorous research is needed before making firm recommendations. If you're considering nutritional supplements during cancer treatment, consult with qualified integrative oncology practitioners who can guide evidence-based decisions.

This umbrella review synthesized evidence from 52 systematic reviews encompassing 250 RCTs evaluating 18 nutritional supplements for 16 cancer supportive care indications. Using AMSTAR-2 assessment, nearly all reviews were rated low/critically low quality. Moderate-certainty evidence supported amino acids and oral proteolytic enzymes for radiation-induced dermatitis severity reduction, and N-acetyl cysteine for chemotherapy-induced peripheral neuropathy (CIPN) prevention in gastrointestinal cancer patients. Low to very low certainty evidence suggested potential benefits for glutamine, zinc, probiotics, and melatonin in oral mucositis; vitamin E, omega-3 fatty acids, glutamine, and other amino acids for CIPN prevention. High-dose vitamin A was associated with serious adverse events; zinc and vitamin E showed dose-related toxicity. Most supplements demonstrated only minor adverse effects. The predominance of low-certainty evidence precludes definitive clinical recommendations. The authors emphasize need for higher-quality research evaluating efficacy, safety, and potential interference with conventional cancer treatments before widespread clinical implementation.