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Vitamin pills a waste of
time and money, says study
By David Derbyshire, Science Correspondent
(Filed: 05/07/2002)
Vitamin pills are "a waste of time" and do not reduce
the risk of heart disease or cancer, according to one of the biggest
studies into food supplements.
A five-year study involving more than 20,000 people
found that a daily dose of three vitamin supplements made no difference
to heart disease, cancer or mental decline. Prof Rory Collins, a
co-author of the report at Oxford University's Clinical Trial Service,
said: "Over five years we saw absolutely no effect. Vitamin pills are a
waste of time.
"There was no evidence of any protective effect against
heart disease, cancer or any other outcome. They are safe, but they are
useless."
The findings come from the British Heart Protection
Study which followed 20,000 people aged 40 to 80 for an average of five
years. The study looked at the effect of cholesterol-lowering statins,
and a cocktail of vitamin C, vitamin E and beta carotene.
At the end of the trial, people taking vitamins had
exactly the same risk of heart disease, cancer, cataracts, bone
fractures, asthma and mental decline as those who took a placebo. In
contrast, statins reduced the risk of heart disease and stroke by around
one third.
Dr Jane Armitage, of Oxford University, and a co-author
of the paper published today in the Lancet, said: "This study found that
they [vitamins] are a waste of money. People would be far better off
spending the money on fresh fruit and vegetables.
"There have been other studies into vitamins, but this
is the first major study that has looked at a cocktail of vitamins. We
were disappointed, but by the end not very surprised. At the beginning
there was enormous optimism that this would be the answer."
The vitamins used in the study are anti-oxidants, which
help mop up harmful free radicals. When the "bad" form of low density
lipoprotein (LDL) cholesterol oxidises, it is more likely to be laid
down on the lining of artery walls, increasing the risks of heart
disease and stroke. The three vitamins were thought to prevent LDL
cholesterol oxidising.
Prof Collins conceded that some of the benefits might
emerge many years later. "But there was no evidence of a delayed
effect," he said. "Cholesterol-lowering drugs worked within a year and
had major effects after five years."
There are growing suspicions among food scientists that
the beneficial effects of fresh fruit and vegetables cannot easily be
replicated in pills.
Dr Ann Walker, a food nutritionist at Reading
University and a spokesman for the British Proprietary Association,
which represents the food supplement industry, said the doses of
vitamins might have been too low to help people already suffering from
chronic heart disease.
"For other diseases such as cancer, what matters is a
lifetime's intake of anti-oxidants, not what happens over five years,"
she said.
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