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Cruciferous vegetables and colo-rectal cancer

Published online by Cambridge University Press:  07 March 2007

Anthony Lynn
Affiliation:
The Robert Gordon University, St Andrew Street, Aberdeen AB25 1HG, UK
Andrew Collins
Affiliation:
University of Oslo, Blindern, N-0316 Oslo, Norway
Zoë Fuller
Affiliation:
The Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, UK
Kevin Hillman
Affiliation:
The Scottish Agricultural College, Craibstone, Aberdeen AB21 9YA, UK
Brian Ratcliffe
Affiliation:
The Robert Gordon University, St Andrew Street, Aberdeen AB25 1HG, UK
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Abstract

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Cruciferous vegetables have been studied extensively for their chemoprotective effects. Although they contain many bioactive compounds, the anti-carcinogenic actions of cruciferous vegetables are commonly attributed to their content of glucosinolates. Glucosinolates are relatively biologically inert but can be hydrolysed to a range of bioactive compounds such as isothiocyanates (ITC) and indoles by the plant-based enzyme myrosinase, or less efficiently by the colonic microflora. A number of mechanisms whereby ITC and indoles may protect against colo-rectal cancer have been identified. In experimental animals cruciferous vegetables have been shown to inhibit chemically-induced colon cancer. However, the results of recent epidemiological cohort studies have been inconsistent and this disparity may reflect a lack of sensitivity of such studies. Possible explanations for the failure of epidemiological studies to detect an effect include: assessment of cruciferous vegetable intake by methods that are subject to large measurement errors; the interaction between diet and genotype has not been considered: the effect that post-harvest treatments may have on biological effects of cruciferous vegetables has not been taken into account.

Type
Postgraduate Symposium
Copyright
Copyright © The Nutrition Society 2006

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