Less Salt, More Potassium for Heart Health

Blood pressure may improve with less salt and more potassium in diet

(RxWiki News) Put down that saltshaker—it could save your life. Growing evidence shows cutting back on salt consumption reduces blood pressure and, in turn, the risk of stroke and heart disease.

Two new studies show that a reduction in salt intake may help blood pressure and one recent report finds that lower potassium consumption is linked to higher blood pressure.

Based on information in these investigations, the World Health Organization is now recommending individuals reduce their salt consumption to less than one teaspoon per day.

"Cut back on salt intake to help lower blood pressure."

Feng He, PhD, a senior research fellow at Wolfson Institute of Preventive Medicine, Barts and The London School of Medicine and Dentistry at Queen Mary University of London, and his colleagues led one of the studies.

They examined the effects of modest salt reduction on blood pressure, hormones, and blood fats (lipids) from 34 trials involving over 3,000 adults.

Dr. He and his team concluded that modest reduction in salt for four or more weeks led to significant drops in blood pressure in people with both elevated and normal blood pressure.

“The current recommendations to reduce salt intake from 9-12 to 5-6 grams per day will have a major effect on blood pressure, but a further reduction to 3 grams [less than a teaspoon] per day will have a greater effect and should become the long term target for population salt intake,” wrote the authors.

In a related study, Nancy J Aburto, PhD, a scientist in the Department of Nutrition for Health and Development at the World Health Organization, and her fellow researchers found that reduced salt intake reduces blood pressure and had no adverse effect on blood lipids, hormone level or kidney function.

They based their conclusions on 56 studies, 37 of which were high quality studies reporting blood pressure, blood lipids, renal (kidney) function and catecholamine levels (hormones produced by adrenal glands).

Dr. Aburto also published a study on potassium intake and health based on 33 trials and involving over 128,000 healthy participants. Potassium is found in most fresh fruits and vegetables and legumes.

The results show that increased potassium intake reduces blood pressure in adults, with no adverse effects on blood lipids, hormone levels or kidney function.

Higher potassium intake was linked with a 24 percent lower risk of stroke in adults and may also have a beneficial effect on blood pressure in children, but more data is needed.

The research also suggested an increased benefit with simultaneous reduction in salt intake.

Based on these studies, the World Health Organization recommends reducing dietary salt intake to 5 grams (about one teaspoon) per person per day. Salt intake in many countries is currently much higher than this.

The WHO believes such a strategy will save millions of lives every year from heart disease and stroke.

Sarah Samaan, MD, cardiologist and physician partner at the Baylor Heart Hospital in Plano, Texas, told dailyRX News, “I think that most people would be shocked to know just how much salt is in their diet. The truth is only about 15 percent of our sodium intake comes from the saltshaker. The rest is hidden in processed snack foods, restaurant meals, pasta sauces, soup, lunch meats, even bread and other baked goods.”

She added that more than 90 percent of Americans—kids included—eat too much salt.

When it comes to potassium, Dr. Samaan says it's easy to get plenty by eating the recommended 5 to 10 servings of fruits and vegetables daily.

The studies were published online in April in BMJ—British Medical Journal.

Review Date: 
April 5, 2013