Explore

Adequate vitamin D status is associated with better outcomes in several cancers and supports immune regulation.

A standard daily multivitamin helps fill everyday nutrient gaps. Large trials (Physicians' Health Study II, COSMOS) found a modest lower rate of total cancer in older adults taking one — helpful, but not a replacement for a healthy diet.

An antioxidant vitamin important for immune function and tissue repair. Diets rich in vitamin C (from fruits and vegetables) are linked to lower risk of some cancers, though supplements have not been proven to prevent cancer.

Folate is a B vitamin essential for copying and repairing DNA correctly. Getting enough folate from food is associated with lower colorectal cancer risk, making it an important part of a protective diet.

A mineral best known for bone health that also has research links to lower colorectal cancer risk. Getting enough calcium — ideally from food — supports the gut lining and bone strength during treatment.

The long-chain omega-3 fats EPA and DHA (from oily fish or fish oil) are anti-inflammatory and support heart and brain health. Research on cancer prevention is mixed, but omega-3s may help reduce inflammation and support appetite and muscle during treatment.

A trace mineral that is part of the body's antioxidant defense (glutathione peroxidase). Adequate selenium from food supports normal cell protection — but more is not better, and supplements have not been proven to prevent cancer.

Beta-glucans in reishi and turkey tail are studied as immune modulators; turkey tail (PSK) is used alongside chemo in parts of Asia.