Hypertension is not a life-threatening cardiovascular event, which may be why your advice to reduce salt intake often makes little impression. But patients’ ears will perk up when you tell them this: New research shows that reducing dietary sodium can lower the chances of an MI or stroke by 25% or more.
Investigators at Harvard Medical School in Boston, the NIH, and a number of other centers contacted 2,415 people (or their relatives) who had completed two trials 10-15 years ago that analyzed the impact of salt reduction on hypertension. People in both trials, which lasted 18-48 months, had been randomized to either their usual diets or to a 25%-35% reduction in sodium. Sodium intake was determined by repeated assessments of 24-hour urinary excretion, an unusually rigorous methodology.
In their follow-up, conducted by phone or mail, researchers determined that 200 trial participants had experienced a cardiovascular event—an MI, stroke, coronary bypass, angioplasty, or death from a cardiovascular cause. The risk of such an event was 25% lower among those in the salt-reduction groups after adjusting for age, race, sex, and other factors. When further adjustments were made, for weight and other issues, the risk fell by 30%.
“Our study provides unique evidence that sodium reduction might prevent cardiovascular disease and should dispel any residual concern that sodium reduction might be harmful,” the researchers concluded (BMJ. 2007: 334:885-895).
Americans get most of their sodium not from the saltshaker but from processed food. Those on a low-sodium diet should avoid ham, hot dogs, lunch meat, sausage, bacon, smoked fish, olives, pickles, canned soups, bouillon, broth, potato chips, and salted nuts.