February 23 2000  UNITED STATES

'Myth' of salt link to blood pressure is attacked

MOVES by British supermarkets to cut the amount of salt in the food
they sell are not based on sound scientific evidence, according to an
American scientist.

For years it has been believed that high salt consumption is a cause
of high blood pressure, but this has never been fully supported by
researchers or data, Dr David McCarron, of Oregon Health Sciences
University, said.

"In recent years the hold of the salt, blood pressure hypothesis has
been severely weakened by a large volume of new information which has
revealed with increasing clarity that, while dietary salt does play a
role, for the general public it is certainly not the arch-enemy of
normal blood pressure regulation," he told the American Association
for the Advancement of Science, meeting in Washington.

Calling the idea a "myth that had become dogma for the medical
community and the public alike", Dr McCarron said that an
international study involving 10,000 people in 52 countries, had
failed to demonstrate the link. "Its investigators concluded that
sodium intake was not significantly related to median blood pressure
or prevalence of high blood pressure," he said.

A number of studies had shown that blood pressure was reduced only
very slightly, by one millimetre of mercury, when salt intake was
reduced by 30 to 50 per cent. Nor was there evidence that reducing
salt intake reduced heart attacks, he said. Some had actually shown an
increase. Diets rich in fruit and vegetables and low in fat were much
more effective, he said.

NIGEL HAWKES