Source: Imperial College London
Summary: A new study suggests, a healthy diet may not offset the effects of a high salt intake on blood pressure.
High blood pressure affects more than one in four adults in the UK and increases the risk of a number of conditions including heart attacks and stroke. It’s thought to have a number of causes, including age, weight and eating too much salt. It’s thought that vitamins and minerals in fruit and vegetables might in some way affect blood vessels, enabling them to lower blood pressure. Previously, experts believed that eating high amounts of fruit and vegetables might help counteract the effect of high salt on blood pressure. A new study by the researchers from a number of institutions, including Imperial College London and Northwestern University, analyzed the diets of over 4,000 people and found that a healthy diet may not offset the effects of a high salt intake on blood pressure. The study findings were published in the journal Hypertension.
The team assessed concentrations of sodium and potassium in the urine samples. Sodium is the main component of salt, while potassium, which is found in green leafy vegetables, has been linked to lower blood pressure. The team also used dietary data to assess the volunteers’ intake of over 80 nutrients that may be linked to low blood pressure, including vitamin C, fibre, and omega-3 fatty acids. Many of these nutrients are found in fruit, vegetables and whole grains. The recommended upper limit of adult salt intake in the UK is 6g a day, around one teaspoon. The study found that average salt intake across the study was 10.7g a day. The average intake for the UK was 8.5g, while the intake for the USA, China and Japan were 9.6g, 13.4g and 11.7g respectively. These findings underscore the importance of reducing salt intake for the prevention and control of prehypertension and hypertension.
Joint lead author, Dr. Queenie Chan said, “We currently have a global epidemic of high salt intake – and high blood pressure. This research shows there are no cheats when it comes to reducing blood pressure. Having a low salt diet is key – even if your diet is otherwise healthy and balanced.”
More Information: Jeremiah Stamler et al, “Relation of dietary sodium (salt) to blood pressure and its possible modulation by other dietary factors”, Hypertension (2018). dx.doi.org/10.1161/HYPERTENSIONAHA.117.09928