Question

Choose a phytochemical and discuss its role in cancer prevention. Discuss how to incorporate this into one's diet and how to increase its potency. Please cite references.Choose a phytochemical and discuss its role in cancer prevention. Discuss how to incorporate this into one's diet and how to increase its potency. Please cite references.

Answer 1

Phytochemicals are molecules which occur in the plant kingdom and these are the main compounds which are responsible for the colour, taste and aroma of foods. Phytochemicals protect us from environmental and ingested carcinogens by arming our antioxidant enzymes, enhancing DNA repair pathways and have direct effects on the fundamental hallmarks of cancer progression and metastasis. linical evidence for cancer prevention.

Representative examples of potentially cancer chemopreventive phytochemicals are genistein (soya), curcumin (curry spice turmeric), vitamin C (fruits, vegetables), lycopene (tomatoes), β-carotene (fruits, vegetables), tea catechins such as epigallocatechin gallate (green tea), resveratrol (red grapes, other fruits) and apigenin (leafy vegetables).

Although not all, many studies have linked a higher intake of phytochemical-rich foods, such as vegetables, fruit, legumes, nuts, herbs and spices, with a lower incidence of cancer as highlighted in the latest comprehensive review from the World Cancer Research Fund and other systemic reviews

More specifically, certain elements of food have been addressed within a number of cohort studies. Carotenoids found in leafy green vegetables and carrots have been linked with a lower risk of breast cancer in a recent meta-analysis demonstrated and a lower risk of ovarian and pancreatic cancers,especially among smokers in either questionnaire or serum-based studies, , Higher intake of cruciferous vegetables such as cabbage, cauliflower, Brussel sprouts, radishes and broccoli have been associated with a lower prostate cancer risk, as have foods rich in isoflavones such as pulses and soy products, lycopene rich colourful fruits and tomatoes. Foods with abundant levels of flavonoids such as onions, rich in quercetin, have been shown to reduce the incidence of numerous cancers particularly those arising from the lung, especially amoung smokers. The anthoxanthins, in dark chocolate, have been reported to lower the risk of colon cancer and higher green tea intake lowers the risk of breast, prostate, ovarian and oesophageal cancer, again particularly among smokers and alcoholics.

Reference:

Bjelakovic G, Nikolova D, Simonetti RG et al (2004) Antioxidant supplements for prevention of gastrointestinal cancers: a systematic review and meta-analysis. Lancet 364:1219–1228.

Omenn GS (1998) Chemoprevention of lung cancer: the rise and demise of beta-carotene. Annu Rev Public Health 19:73–99.

World Cancer Research Fund and Institute for Cancer Research (1997) Patterns of diet and cancer. In: Potter JD (ed) Food, nutrition and the prevention of cancer: a global perspective. American Institute for Cancer Research, Washington, DC, pp 20–52.