Potential Synergy of Phytochemicals in Cancer Prevention: Mechanism of Action

Abstract

Epidemiological studies have consistently shown that regular consumption of fruits and vegetables is strongly associated with reduced risk of developing chronic diseases, such as cancer and cardiovascular disease. It is now widely believed that the actions of the antioxidant nutrients alone do not explain the observed health benefits of diets rich in fruits and vegetables, because taken alone, the individual antioxidants studied in clinical trials do not appear to have consistent preventive effects. Work performed by our group and others has shown that fruits and vegetable phytochemical extracts exhibit strong antioxidant and antiproliferative activities and that the major part of total antioxidant activity is from the combination of phytochemicals. We proposed that the additive and synergistic effects of phytochemicals in fruits and vegetables are responsible for these potent antioxidant and anticancer activities and that the benefit of a diet rich in fruits and vegetables is attributed to the complex mixture of phytochemicals present in whole foods. This explains why no single antioxidant can replace the combination of natural phytochemicals in fruits and vegetables to achieve the health benefits. The evidence suggests that antioxidants or bioactive compounds are best acquired through whole-food consumption, not from expensive dietary supplements. We believe that a recommendation that consumers eat 5 to 10 servings of a wide variety of fruits and vegetables daily is an appropriate strategy for significantly reducing the risk of chronic diseases and to meet their nutrient requirements for optimum health.

Asparagus racemosus extract increases the life span in Drosophila melanogaster

“…All the nutriceutical extract of plants are change to have high levels of polyphenols, which possess high antioxidant activities and other health-promoting properties. Phenolic compounds are powerful chain breaking antioxidants in scavenging the radicals [34,35], the flavonoids and phenolics prevent the damage against free radicals [36]. In the present investigation the results reveal the root of A. racemosus contains rich source of phenolics and flavonoids.…”

Fruit and vegetable intake and prostate cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC)

“…Only one small prospective study (139 incident prostate cancer cases) on fruit consumption and prostate cancer risk has been published since then, which also showed no association 22. If there is an association between fruit consumption and prostate cancer risk it might be due to the high content of vitamins (such as vitamin C) and phytochemicals (such as phenolic compounds and carotenoids), which may have anti‐carcinogenic properties 10, 23. However, men who have high fruit intake differ in several respects from men with a low fruit intake and therefore residual confounding cannot be excluded.…”

Dietary Phytochemical Index and the Risk of Breast Cancer: A Case Control Study in a Population of Iranian Women

“…Anticarcinogenic properties of these phytochemicals are attributed to inhibiting phase I enzymes, induction of phase II enzymes, scavenge DNA reactive agents, suppress the abnormal proliferation of early and pre-neoplastic lesions, and inhibit certain properties of the cancer cell (Waladkhani et al, 1998); other mechanisms involved in the preventive effects of phytochemicals against cancer are regulation of steroid hormone and estrogen metabolism, inhibition of cell adhesion and invasion, induction of tumor suppress gene expression, cell cycle arrest and apoptosis, and modulation of some important signal transduction pathways (Liu et al, 2004).…”