FISH DIET CAN REDUCE RISK OF HEART ATTACK

     Research team claims it has proved for the first time that eating fish can significantly reduce the risk of heart attack.
     Team leader announced the finding shown that a diet high in polyunsaturated fats such as fish oil significantly
decrease the incidence of death from heart-rhythm disturbances, which in layman's terms means heart attacks.
     Dr. McLennan, a cardiac physiologist, said that a diet hoigh in polyunsaturated fish fats could alter the composition of heart muscle cells.
     "These changes decrease the likelihood of heart rhythm disturbances and decrease the incidence of the kind of heart attack from which the victim dies quickly," Dr. McLennan said.
     Fish high in oil, such as tuna or mackerel, were the best from this point of view, but not canned tune because the cooking process for canning removes the beneficial oils.
     His team, based in Adelaide, South Australia, used an oily residue from a tune for their experiments with rats that lasted over four years.
     Presenting his findings in Melbourne, Dr. McLennan said his group had obtained "surprising results".
     "Even we were sceptical of them initially. We repeated the results a number of times to confirm their accuracy," he said.
     Dr. McLennan said that previous studies had shown fish oil could decrease atherosclerosis the blocking of coronary arteries by the build up of fatty substances which impair blood flow to the heart.
     But his work was the first to point to the relationship between consumption of fish oil and reduction in heart rhythm disturbances.
     "The study was carried out on four groups of rats fed diets which included fats from different sources saturated fat of animal origin, polyunsaturated fat of plant origin, polyunsaturated fat of fish origin and mixtures of the three.
     The researchers then tried to trigger heart attacks by methods which simulated known cause of heart attack in man, and the incidence and duration of the rhythm disturbance was then assessed.
     Fewer of the animals on polyunsaturated diets reacted to the trigger and those that did had a shorter episode of disturbed rhythm. Animal on a saturated fat diet were more likely to have heart rhythm disturbances and these were longer lasting than those for animals on the mixed and polyunsaturated diets.
     With one method of inducing heart attacks, the rhythm disturbance was significantly reduced both in incidence and duration, by the fish oil but not by the polyunsaturated vegetable oil.
     Dr McLennan said that mortality was significantly increased by dietary saturated fats but there were no deaths in rats fed either of the polyunsaturated diets.