Such a strategy will save millions of lives every year from heart disease and stroke. Much evidence shows that reducing salt intake lowers blood pressure and thereby reduces the risk of stroke and heart disease. Less is known about the potential benefits of increasing potassium intake, but lower potassium consumption has been linked with elevated blood pressure.
The World Health Organisation has therefore set a global goal to reduce dietary salt intake to 5-6 g (about one teaspoon) per person per day by 2025, yet salt intake in many countries is currently much higher than this. The first study examined the effects of modest salt reduction on blood pressure, hormones, and blood fats (lipids) from 34 trials involving over 3,000 adults.
It found a modest reduction in salt for four or more weeks led to significant falls in blood pressure in people with both raised and normal blood pressure. However, the researchers believe current recommendations "are not ideal" and say a further reduction to 3 g per day "should become the long term target for population salt intake."
Lower sodium intake was also associated with reduced risk of stroke and fatal coronary heart disease in adults. "The totality of evidence suggests that reducing sodium intake should be part of public health efforts to reduce blood pressure and cardiovascular diseases, and will likely benefit most individuals,"
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% lower risk of stroke in adults and may also have a beneficial effect on blood pressure in children, but more data is needed.
The World Health Organisation therefore recommends to reduce dietary salt intake to less than 5 g (about one teaspoon) per person per day and set a global goal of a 30% relative reduction in mean adult population intake of salt by 2025, with the aim of achieving the WHO's salt intake recommendation, yet salt intake in many countries is currently much higher than this.