Immunonutrition and cancer.

The immune system is the body's primary defence against invading pathogens, non-self components and cancer cells. Inflammatory processes, including the release of pro-inflammatory cytokines and formation of reactive oxygen and nitrogen species, are an essential part of these processes. Although such actions are usually followed rapidly by anti-inflammatory effects, excessive production of pro-inflammatory cytokines, or their production in the wrong biological context may lead to situations of chronic inflammation. Whether such conditions arise as a result of exogenous chemicals, invading pathogens or disease processes, the long-term implications include an increased risk of cancer. A number of nutrients have the ability to modulate immune response and counter inflammatory processes. Zinc, epigallocatechin galate (EGCG), omega-3 polyunsaturated fatty acids and probiotics all act differently to modulate immune response, but all appear to have the potential to protect against cancer development and progression. We suggest that immunonutrition may provide a less invasive alternative to immunotherapy in protection against cancers associated with chronic inflammation.