Cancer Advisor | One Day MD

Medically reviewed by Dr. Frank Yap, MD  |  Written by OneDayMD Editorial Team  |  Last updated October 2026 Quick Answer Of the 17 supplements reviewed here, the deepest human evidence supports vitamin D3 (with K2 and magnesium) , polysaccharide-K (PSK) from turkey tail as an add-on to chemotherapy in Japanese trials, berberine for preventing colorectal adenoma recurrence, omega-3 fatty acids , curcumin and green tea EGCG . Even these show mixed rather than uniformly positive results. Melatonin looked promising in small trials, but the largest randomized trial found no benefit in early-stage lung cancer. A few supplements, namely high-dose beta-carotene, vitamin E and long-term high-dose B6/B12 , have been linked to higher cancer risk in specific groups. No supplement replaces conventional cancer treatment, and antioxidant pills are generally discouraged during chemotherapy or radiotherapy unless your oncologist directs otherwise. This is educatio...

OneDayMD Cancer Resource Library · Network Index · Published September 17, 2026 · Last reviewed and updated October 2026 (v2.1) Cancer information is no longer confined to a single textbook, treatment guideline, or hospital website — and cancer guides should not be limited to oncologists. Modern oncology now spans pathology, staging, molecular biomarkers, precision medicine, prevention, surgery, radiation, chemotherapy, targeted therapy, immunotherapy, cellular therapy, cancer metabolism, treatment resistance, supportive care, and clinical research. This OneDayMD guide brings those subjects together in one navigable resource. Rather than hundreds of disconnected articles, it offers a pathway through the evidence and links directly to deeper OneDayMD, SmartCancer, and Cancer Advisor resources. Quick Answer This page is a map, not a single treatment guide — it connects the OneDayMD network's cancer content by the question you're actually asking. Newly diagnosed and w...