Functional foods and their role in cancer prevention and health promotion: a comprehensive review.

Following cardiovascular disease, cancer is the second leading cause of death in most affluent countries. The 13.3 million new cases of cancer in 2010 were predicted to cost US$ 290 billion, but the total costs were expected to increases to US$ 458 billion in the year 2030 on basis of World Economic Forum in 2011. More than half of all cancer cases and deaths worldwide are consider being preventable. From its inception, the disease control priorities series has focused attention on delivering efficacious health interventions that can result in dramatic reductions in mortality and disability at relatively modest cost. The approach has been multidisciplinary, and the recommendations have been evidence-based, scalable, and adaptable in multiple settings. Better and more equitable health care is the shared responsibility of governments and international agencies, public and private sectors, and societies and individuals, and all of these partners have been involved in the development of the series. Functional foods are foods and food components that supply health benefits beyond basic nutrition. It's-believed these functional foods do more than simply provide nutrients because they help to maintaining health and thereby reducing the risk of disease. There are some reported evidences showing association between functional foods and cancer. For example, S-ally cysteine of garlic and lycopene from tomatoes in combination form suppressed the development of chemically induced gastric cancer by modulation of apoptosis-associated proteins (reduced Bcl-2/Bax ratio and up-regulation of Bim and caspases 8 and 3) at considerably lower intakes than when these substances were given in isolation. Similarly, vitamin D3 with genistein in combination form precipitated a growth inhibition of prostate cancer cells at much lower concentration than when these substances were provided individually. There are very few studies conducted worldwide to see the effects of functional foods on health or cancer or related states. This review, presents the complex patterns of cancer incidence and death around the world and evidence on effective and cost-effective ways to control cancers. The evaluation of cancer will indicate where cancer treatment is ineffective and wasteful, and offer alternative cancer care packages that are cost-effective and suited to low-resource settings. In the present paper, cancer prevention by functional foods is reviewed and the possible mechanisms of action are described.