Nutraceuticals and Oral Supplements in Cancer Prevention: A Narrative Review

Background: Epidemiological studies have shown that food is a compelling means of maintaining a state of well-being and preventing diseases. Many malignant diseases are related to nutrition, and the nutrient-organism interaction could define the balance between health and disease. Nutrients and dietary components influence epigenetic phenomena and modify drug response so that food-organism interactions may influence individual predisposition to disease and its potential therapeutic response. Aims: In this review, we highlighted emerging opinions and data on a large cluster of nutraceuticals, as well as functional foods and specific dietary patterns, with respect to cancer, including breast, pancreas, prostate, and colorectal. Only those nutraceuticals and nutritional supplements yielding sufficient and convincing data have been reported in this review; molecules with inconclusive clinical evidence will not be discussed. Conclusion: Growing and accumulating evidence is validating the use of nutraceuticals in cancer settings. However, a knowledge gap remains in terms of causal evidence for several compounds where a window for further clinical studies is left.