While some evidence suggests that obesity coupled with a lack of exercise is an important factor involved in the development of high blood pressure, stronger evidence indicates that salt intake is more strongly related to the development of hypertension, particularly the rise in blood pressure with age.
Hypertension can be defined as a blood pressure of 140/90 mmHg or higher, however the risk of CVD starts at a systolic blood pressure of around 115mmHg. Raised blood pressure is the major cause of the development of cardiovascular disease and is the biggest cause of death in the world through the strokes and heart attacks it causes.
Approximately one in four adults in the UK have high blood pressure with many more that are unaware they have the condition.
Who is most at risk of high blood pressure?
Anyone is at risk of a high blood pressure, as blood pressure starts to increase from childhood. People with a high salt diet, pregnant women and people of black African descent are particularly susceptible to high blood pressure.
High blood pressure is an important risk factor for a range of conditions. These include strokes, vascular dementia, diabetes, kidney disease, heart disease and mobility problems. People who already have these conditions may find a reduced salt diet beneficial in the long run.
How does salt contribute?
A high salt diet disrupts the natural sodium balance in the body. This causes fluid retention which increases the pressure exerted by the blood against blood vessel walls (high blood pressure). For every one gram of salt we cut from our average daily intake, there would be approximately 6,000 fewer deaths from strokes and heart attacks each year in the UK. It has been estimated that a reduction in salt intake from 10g a day to 6g will reduce blood pressure and could lead to a 16% reduction in deaths from strokes and a 12% reduction in deaths from coronary heart disease. This would prevent approximately 19,000 stroke and heart attack deaths in the UK each year and 2.6 million each year worldwide. Reducing salt is one of the quickest ways to reduce your blood pressure, particularly if you already have high blood pressure.
Current salt intake & dietary advice
Almost everyone in the UK (and the rest of the Western world) eats too much salt. The daily recommended amount in the UK is no more than 6 grams a day; the current average salt intake is around 8g salt a day although many people are eating more than this.
People with or considered at risk of high blood pressure should take extra care to ensure that they keep their salt intake below the recommended maximum of 6g. This can be achieved by simple changes, such as consuming less processed foods and checking product labels before purchase.