Bramen, frambozen en blauwe bessen tegen kanker.*
Uit dierenstudies was al gebleken dat bramen, frambozen en blauwe en zwarte bessen de kans op kanker in het spijsverteringssysteem zoals, mond, slokdarm en darmen flink kan verminderen. Dit fruit bevat veel stoffen die kanker en de groei daarvan tegengaan zoals vitaminen, calcium, selenium, carotenen, luteïne en veel andere bioactieve stoffen waaronder de anthocyanen. Hoe donkerder het fruit hoe meer van deze bioactieve stoffen zich in het fruit bevinden. Dieren, die 5 tot 10% van hun dagelijkse voeding dit fruit kregen reduceerde daarmee het risico op het krijgen van kanker in het spijsverteringssysteem wel met 45-80%. De voorlopige uitkomsten van een onderzoek onder mensen die ook 5-10% van hun dagelijkse voeding dit fruit nemen blijken vergelijkbare resultaten te geven als uit de dierenstudies.
Black
Raspberries May Slow Growth Of Colon, Other Cancers
For several years, our laboratories have studied the
ability of freeze-dried berries (black raspberries, strawberries and
blackberries) to inhibit cancer in the esophagus, colon and oral cavity. Berries
contain a number of agents that prevent cancer including vitamins A, C, and E;
calcium and selenium; ß-carotene, α-carotene and lutein; and many phenolic
compounds which have high anti-oxidant potential. The most abundant phenols are
the anthocyanins which give berries their color. In general, dark berries have
higher contents of anthocyanins and anti-oxidant potential than light berries.
The addition of powdered berries at 5 and 10% of the diet of animals reduces
their risk for development of cancer in the oral cavity, esophagus and colon by
45-80%. Berries function to reduce the amount of genetic (DNA) damage produced
in these tissues by chemical carcinogens, including carcinogens in tobacco smoke
and in the diet. They also reduce the growth rate of precancerous cells, in
part, by reducing the expression of genes associated with cell growth. Berries
also inhibit the expression of other genes associated with cancer development
including genes involved in inflammatory processes and in the formation of new
blood vessels (angiogenesis).
In a preliminary trial in humans, berries were found to be well tolerated at
doses similar to those used in animals. They reduced cellular damage caused by
oxidative radicals which is consistent with their anti-oxidant potential. In
view of these results, several human clinical trials are ongoing to determine
the ability of freeze-dried berries to inhibit the development of precancerous
lesions in the oral cavity, esophagus and colon of humans. Preliminary results
suggest that berries influence the expression of many of the same genes in
humans as they do in animals. An apparent advantage of this "food-based"
approach to disease prevention is the relative absence of toxicity associated
with the long-term consumption of berries by humans.
Ohio State University Medical Center
450 W. 10th Ave.
Columbus, OH 43210
United States (April 2007)