Food manufacturers should be encouraged not only to cut salt, but also to increase potassium levels in foods, according to new studies published in the British Medical Journal.
The food industry has been under pressure to reduce the amount of salt in its products, because an estimated 75% of salt intake comes from processed foods, including products like bread and cheese, which are major contributors to salt consumption in Western diets. Sodium has been linked to increased blood pressure, while potassium is thought to have the opposite effect, meaning that getting the right balance of the two nutrients is considered important for optimum health.
Examining studies involving more than 128,000 participants, a study on the effects of potassium intake found that those with the highest potassium intake had a 24% lower risk of stroke. It also found that high potassium intake reduced blood pressure in people with hypertension, and had no adverse effects on people with normal blood pressure and kidney function.
“These results suggest that increased potassium intake is potentially beneficial to most people without impaired renal handling of potassium for the prevention and control of elevated blood pressure and stroke,” the study’s authors wrote.
In a separate study examining salt intake , researchers examined 34 trials looking at the effects of a modest reduction in salt intake among more than 3,000 adults.
“Modest reduction in salt intake for four or more weeks causes significant and, from a population viewpoint, important falls in blood pressure in both hypertensive and normotensive individuals, irrespective of sex and ethnic group,” they found.
Consensus Action on Salt and Health (CASH) said in a statement that the studies reinforced recommendations that most individuals should cut their salt intake and increase consumption of fruits and vegetables, which are a major source of potassium. In addition, it said it provided governments with further impetus to set salt targets for the food industry.
“These studies show that it is absolutely vital that the government forces the food industry to gradually reduce the amount of salt they add to our food by setting new targets,” said professor Graham MacGregor, professor of cardiovascular medicine at the Wolfson Institute, Barts and London Hospitals, and chairman of CASH.
“80% of our salt intake is already hidden in food, i.e. the majority of consumers have no choice. If the food industry does not cooperate then the government must legislate, as has occurred in other countries (Portugal and South Africa).”