A natural pesticide falcarinol present in carrots can reduce cancer
development finds a team of researchers, from the University of Newcastle upon
Tyne in England and from Denmark.
A natural pesticide falcarinol present in carrots can reduce cancer
development finds a team of researchers, from the University of Newcastle upon
Tyne in England and from Denmark. Falcarinol reduced the risk of cancer
developing in rats by one third. Although experts have recommended that people
eat carrots for their anti-cancer properties, it has not been known exactly what
component of the vegetable has this effect. The study results, published in the Journal
of Agricultural and Food Chemistry, are significant as they could
contribute to healthy eating advice for consumers and recommendations for
growers and may eventually aid the development of anti-cancer drugs.
Falcarinol protects carrots from fungal diseases, such as liquorice rot that
causes black spots on the roots during storage. The scientists investigated the
compound after a previous published study suggested it could prevent the
development of cancer.
The research team carried out tests on 24 BDIX rats with pre-cancerous
tumours in laboratory conditions. They divided them into three groups of 8 and
fed them rat feed supplemented with 10% (w/w) freeze-dried carrots containing 35
µg falcarinol naturally or 10% maize starch to which was added 35 µg
falcarinol/g purified from carrots, or 10% maize starch alone.
The team found that, after 18 weeks, rats who ate carrots along with their
ordinary feed and the group which consumed falcarinol with their feed were one
third less likely to develop full-scale tumours than the rats in the control
group. The number of small aberrant crypt foci, precursors of tumours, was
unaffected by the diet.
Dr Kirsten
Brandt, a senior lecturer with Newcastle University's School
of Agriculture, Food and Rural Development, carried out the research with
the University of Southern Denmark and the Danish Institute of Agricultural
Sciences. She said: "We already know that carrots are good for us and can
reduce the risk of cancer but until now we have not known which element of the
vegetable has these special properties.
"Our research allows us to make a more qualitative assessment of the
vegetables we are eating, rather than quantitative. We now need to take it a
step further by finding out how much falcarinol is needed to prevent the
development of cancer and if certain types of carrot are better than others, as
there are many varieties in existence, of different shapes, colours and sizes.
"We could also expand our research to include other vegetables. For
consumers, it may soon no longer be a case of advising them to eat five portions
of fruit and vegetables per day but to eat particular types of these in certain
quantities. The research could also lead to more tailored advice for growers
regarding the methods they should use when growing vegetables."
The experiment was conducted using raw carrots so researchers do not yet know
if eating boiled carrots or drinking carrot juice, for example, would have the
same effect.
Dr Brandt, who says she eats "more carrots than most" and grows her
own organic varieties, recommended that consumers should eat one small carrot
every day, together with other vegetables and fruits, to benefit from their
health-giving properties.
Falcarinol is toxic in large amounts but to obtain a lethal dose you would
have to eat 400 kilograms of carrots at once. Researchers suspect it is
effective because it stimulates mechanisms in the body that fight cancer,
although they have yet to carry out a detailed analysis in this respect.
To search previous research by Kirsten Brandt, go to the quicksearch
page choose 'author search' and enter 'Brandt, K.' into the box. To get
papers on falcarinol select 'free text search' and enter 'falcarinol'.
"Inhibitory Effects of Feeding with Carrots or (-)-Falcarinol on
Development of Azoxymethane-Induced Preneoplastic Lesions in the Rat Colon"
by Kobak-Larsen, M.; Christensen, L. P.; Vach, W.; Ritskes-Hoitinga, J.; and
Brandt, K. is published in J. Agric. Food Chem.; (Article); (2005); ASAP
Article; DOI: 10.1021/jf048519s
Abstract
Contact: Dr Kirsten Brandt, School of Agriculture, Food and Rural
Development, University of Newcastle upon Tyne, Agriculture Building, Newcastle
upon Tyne NE1 7RU, United Kingdom
Email: Kirsten.brandt@ncl.ac.uk