Health
The humble broad bean might
help to prevent bowel cancer - the second most common cause of deaths from
cancer in the UK, scientists have claimed.
Researchers from Hammersmith
Hospital and the Imperial College of Science, Technology, and Medicine,
London, assessed the effects of dietary lectins on the behaviour of cancer
cells in the colon.
Lectins are proteins found in
many plant foods, including broad beans.
They attach themselves to
carbohydrate molecules, which are then absorbed by the cells lining the bowel
during digestion.
The findings, published in
the medical journal Gut, showed that broad bean and mushroom lectins were able
to halt or even reverse the cancer process.
A normal healthy cell is said
to be well differentiated, meaning that its characteristic features and
structures are intact, enabling it to function properly.
Loss of differentiation is a
hallmark of cancer cells.
Cancer halted
The broad bean and mushroom
lectins were able to increase the differentiation of cancer cells, indicating
that the cancer process was either being halted or reversed.
The lectins also seemed to
inhibit cell multiplication, another hallmark of cancer cells.
The way in which lectins
attach themselves to the carbohydrate molecules may be particularly important
in the development of cancer, say the authors, because these molecules are
very active in the processes that turn on and switch off cell growth.
It is the mis-firing of this
process that is believed to cause cancer.
Lead researcher Professor
John Calam said: "It is well known that diets high in fruits and vegetables
protect against many types of cancer, including bowel cancer.
"The lectin effect may be one
of the reasons why."
