Salt may affect more than blood pressure: study

WASHINGTON (Reuters) - Consuming less salt can not only lower blood pressure, but may reduce the risk of heart disease overall, researchers reported on Thursday.

They found that people with borderline-high blood pressure who reduced their sodium intake by 25 to 35 percent lowered their risk of total cardiovascular disease by 25 percent. And this lower risk lasted for 10 to 15 years.

Dr. Nancy Cook and colleagues at Brigham and Women's Hospital and Harvard Medical School in Boston studied more than 3,000 people who took part in a study of a low-salt diet and its effects on high blood pressure.

Those who were assigned to a low-salt diet had a lower risk of all various kinds of cardiovascular disease even 10 to 15 years later, they report in the online version of the British Medical Journal.

They were also 20 percent less likely to have died than people assigned to a normal diet.

"Our study provides unique evidence that sodium reduction might prevent cardiovascular disease and should dispel any residual concern that sodium reduction might be harmful," they wrote.

Salt intake is clearly linked to high blood pressure and the National Heart, Lung and Blood Institute, which paid for the study, recommends that Americans cut down on sodium.

More than 65 million U.S. adults -- one in three -- have unacceptably high blood pressure, above levels of 140/90, the NHLBI said. Another 59 million have prehypertension -- defined as blood pressure of 120/80 or above.

The average U.S. and British diets contain far more than the 2,300 mg daily recommended by the NHLBI and expert groups.

Cook's team said salt may affect artery and heart health by ways that go beyond blood pressure. Sodium may make blood vessels less able to expand and contract and may toughen heart cells, they said.