Fresh
berries can help prevent or delay the onset of atherosclerosis,
the narrowing of the arteries, says a team of international
researchers.
Blackberries seem to have the
most effect, followed by red raspberries, sweet cherries,
blueberries and strawberries, says Edwin Frankel at the
University of California at Davis, a co-author of a study on the
fruit.
According
to Frankel, the current hypothesis about the cause of
atherosclerosis is not only the amount of cholesterol in the
arteries, but cholesterol's susceptibility to oxidation.
"It's the oxidation of LDL that
triggers the beginning of plaque formation in the arteries, and
it is now recognized that if you prevent this process, you also
delay the onset of atherosclerosis," explains Frankel.
The
researchers found that the berries "are all very rich sources of
phenolic compounds which are very potent antioxidants in our
system" – bringing them in the same range as red grapes and wine
as anti-oxidants.
The berries inhibited the
oxidation of LDL in the in-vitro studies by 55 to 84 per cent,
with blackberries being the most effective. That compares to 93
per cent by red grapes and wine, and 55 per cent in ascorbic
acid (vitamin C), an established antioxidant.
So does
that mean we should eat more berries for the good of our hearts?
Frankel says they'll have to
prove that berries are powerful antioxidants in practice and not
just in the lab before he can make such a recommendation. But
until then, a diet rich in fruits and vegetables in general is
recommended by doctors to maintain good health.
The senior author
of the study is I. Marina Heinonen from the University of
Helsinki. Anne Meyer from the Technical University of Denmark is
the other co-author.
