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If this either leads to the end of shark-finning and helps the market/demand for Shark-fin Soup dry up, I, for one, will be a very happy man....

Eating swordfish and shark can 'increase risk of heart attacks'
By David Derbyshire, Science Correspondent
(Filed: 28/11/2002)

People who eat too much shark, swordfish and marlin may be putting themselves at risk of a heart attack, a study has shown.

Although fish oils protect against heart disease, researchers have discovered that the high mercury concentrations in some species can outweigh the benefits.

The authors of the study said warnings on mercury might need to be extended to everyone and not just limited to children and woman about to have children as first thought.

The mixed message is bound to add to consumer confusion over how much fish to eat. But health experts said the existing advice - two portions a week including one portion of oily fish - still stood.

Mercury builds up in body tissue of fish swimming in contaminated waters. Predatory and long-lived fish have the highest levels.

Under the current guidelines, children under 16 and pregnant women and women planning to have a baby are advised to steer clear of shark, swordfish and marlin. Other adults are advised to have just one portion a week.

The study, published today in the New England Journal of Medicine, looked at mercury levels in 1,400 men from eight countries including Britain. Mercury levels were 15 per cent higher in men who had suffered from heart disease than healthy men.

Although mercury is known to damage developing nervous systems, the new study suggests it can also cause heart disease at concentrations "more typical of the levels in the diet of people in Western countries".

Researchers took into account the fact that men may eat more fish after a heart attack.

Fish with relatively high mercury levels include swordfish, shark and king mackerel, while tuna, marlin and red snapper have "intermediate" concentrations.

Prof Rudolph Riemersma, of the University of Edinburgh cardiovascular research unit and a co-author of the paper, said: "We do not advise people to stop eating fish and our analyses are consistent with a protective effect of dietary fish as long as it is not contaminated by mercury."

The team believe that mercury counters the benefits of omega 3 fatty acid in fish.

The Food Standards Agency is reviewing its advice on fish in the light of recent studies.

Belinda Linden of the British Heart Foundation, which partly funded the study, said: "These findings do not affect our advice for people to try to eat fish twice a week, including one portion of oily fish such as sardines and mackerel. This quantity should offer the benefits of omega 3 oils in fish while avoiding any potential harmful effects."

A second study reported in the same journal on 470 men with heart disease found no link between mercury and heart attacks, but concluded that a weak relation could not be ruled out.

For more on the effects of high-level mercury poisoning, check-out the following URL:


(Edited by Bren Tierney at 1:51 am on Nov. 29, 2002)

(Edited by Bren Tierney at 12:52 pm on Nov. 29, 2002)

(Edited by Bren Tierney at 12:53 pm on Nov. 29, 2002)

Gone...and probably best forgotten
1,403 Posts
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Hear, hear Bren.  Stop the finning trade altogether.
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