Reducing Salt Intake Has an Important Blood-Pressure-Lowering Effect in Individuals Already on Drugs for Raised Blood Pressure, According to New Research by Action on Salt
NEW research by Action on Salt (the expert research group based at Queen Mary University of London), published in the journal Hypertension, has confirmed that halving salt intake can significantly lower blood pressure in individuals already taking treatment for hypertension (high blood pressure).
This comprehensive study, which reviewed and combined results from 35 clinical trials, provides strong evidence that salt reduction remains an effective strategy for managing blood pressure in those on treatment. The research demonstrates that for every 3 grams of salt reduction, there is an average decrease of approximately 3.5 mmHg in systolic blood pressure (the top number) and 2 mmHg in diastolic blood pressure (the bottom number). These findings are consistent with prior studies on individuals not taking blood pressure treatment, underscoring the universal benefit of salt reduction.
In simple terms, the research shows that when people cut back on salt in their diet, their blood pressure goes down. This means that reducing salt can help lower blood pressure, making it easier to manage and reduce the risk of heart problems.
Key Findings:
A novel aspect of this study is its exploration of how sodium reduction interacts with various classes of blood pressure-lowering drugs. The research shows that the effect of salt reduction varies depending on the type of drugs. Significant blood pressure reductions were observed in patients taking β-blockers, Renin-Angiotensin-Aldosterone System (RAAS) inhibitors, or a combination therapy involving thiazide diuretics and RAAS inhibitors. those on calcium channel blockers (CCBs) or diuretics alone experienced a smaller fall in blood pressure.
Implications for Public Health and Clinical Practice:
The findings underscore the importance of public health strategies that promote reduced salt intake across all populations, including those already managing high blood pressure with drugs. By integrating salt reduction into the standard care for individuals with high blood pressure, there is potential for better blood pressure control, reduced reliance on drugs, and overall lower healthcare costs.
This study, which coincides with Blood Pressure’s UK’s Know Your Numbers! Week, provides critical insights for future guidelines on blood pressure management, highlighting the role of diet in complementing pharmaceutical interventions. Action on Salt and Blood Pressure UK are now advocating for stronger public health initiatives to lower salt consumption and calls for updated clinical recommendations that reflect these new findings.
Dr Jing Song, Postdoctoral Research Fellow at the Research Action on Salt and Obesity Unit at Queen Mary University of London, says, “Incorporating salt reduction into the routine care of individuals with high blood pressure reinforces the significance of public health initiatives aimed at lowering salt consumption across the population.”
Dr Pauline Swift, Chair of Blood Pressure UK explains: “Reducing salt intake is the most cost-effective way to lower blood pressure and prevent deaths and disabilities from stroke, heart and kidney disease. Each one-gram-per-day reduction in population salt intake could save over 4,000 premature deaths annually, according to the Department of Health & Social Care. It’s imperative that our new government assists the public in cutting salt consumption by enforcing strict targets to compel the food industry to use less salt in their products."
Professor Graham MacGregor, Professor of Cardiovascular Medicine at Queen Mary University of London, Chair of Action on Salt, says: “Reducing salt intake is not just beneficial, but essential for managing high blood pressure, even in patients already on drugs. Both public health policymakers and clinicians should prioritise salt reduction strategies, which could lead to significant improvements in cardiovascular health and a reduction in the need for drugs."
Reference: Jing Song, Liangkai Chen, Hui Xiong, Yuan Ma, Sonia Pombo-Rodrigues, Graham A. MacGregor, Feng J. He. Blood Pressure–Lowering Medications, Sodium Reduction, and Blood Pressure. Hypertension, doi:10.1161/HYPERTENSIONAHA.124.23382, https://www.ahajournals.org/doi/10.1161/HYPERTENSIONAHA.124.23382
