LONDON, March 13: A low-salt diet may not be so healthy after all. Defying a generation of health advice, a controversial new study concludes that the less salt people eat, the higher their risk of untimely death.The report does not necessarily mean people should suddenly lunge for the salt shaker but it does cast doubt on an item of standard dietary wisdom.
The study, led by Dr Michael Alderman, chairman of epidemiology at Albert Einstein School of Medicine in New York and president of the American Society of Hypertension, suggests the US Government should consider suspending its recommendation that people restrict the amount of salt they eat. ``It is possible that the harm of a low-sodium diet may outweigh its benefit,'' the study said. The study, published in the Lancet, a British medical journal, suggests that no single level of sodium will be appropriate for every person in all circumstances. It said the data provide no support for a blanket recommendation regarding dietary sodium.
``The lower thesodium, the worse off you are,'' Alderman said. ``There's an association. Is it the cause? I don't know. Any way you slice it, that's not an argument for eating a low-sodium diet.''
Alderman examined the relationship between sodium intake and death among 11,346 Americans evaluated in the 1970s by the US Government's national health and nutrition examination survey.
By 1992, 3,923 of them had died. He found there were 19 deaths for every 1,000 years of life in the people with the highest salt intake, compared to 23 in those who ate the least salt.
Overall, a 1,000 mg increase in dietary salt was associated with a 10 per cent reduction in mortality.
The link between low-salt diets and death held up even after the researchers factored in people's blood pressures, cholesterol levels, age, gender, economic status and mineral deficiencies.
The study was denounced by some who said the salt consumption information in the original government survey on which the research is based was too inaccurate becauseparticipants had underestimated the amount of salt they were eating.
There are major methodological flaws which makes meaningful interpretation of this paper virtually impossible,'' said Dr Paul Elliott, an epidemiologist at London's Imperial college and one of the authors of a key study on which conventional wisdom is based.
Dr Graham Macgregor of St George's hospital in London agreed, saying he believed the link could have been a statistical fluke.
Macgregor and Elliott also noted Alderman's past association with the food study, saying the criticism was ``unfair and irrational.''
Health officials, however, said the study does not persuade them to reconsider policy. Based on several studies showing a restricted sodium diet can lower blood pressure, US health officials recommend Americans restrict the amount of salt in their diets to no more than 6 grams, or one teaspoon, per day. The average person eats about 12 grams of salt a day, and about 80 per cent of that comes from processed foods. Low-sodiumproponents say ample indirect evidence exists that lower-salt diets save lives through lowered blood pressure. High blood pressure is associated with a higher risk of stroke and heart attack. About 80 per cent of the western world's population has higher blood pressure than it should, Macgregor said.
Copyright © 1998 Indian Express Newspapers (Bombay) Ltd.
Copyright © 1998 Indian Express Newspapers (Bombay) Ltd.
