A recent study published in the Journal of the American Medical Association reveals that reducing daily table salt intake by about one teaspoon can lead to a blood pressure decrease equivalent to that achieved with prescription antihypertensive medications. The research, conducted by a team led by Dr. Deepak Gupta at Vanderbilt University Medical Center, involved 213 participants aged 50 to 75, including individuals already on blood pressure medication. Each participant underwent both a high-sodium and a low-sodium diet for one week each, with the low-sodium diet resulting in consistent blood pressure reduction across all groups, irrespective of baseline measurements or medication use.
The study's findings underscore the significant impact of dietary salt reduction on blood pressure, challenging the notion that its benefits are limited to those not taking hypertension medications. The mechanism by which excess salt raises blood pressure remains under investigation, with a prevailing hypothesis suggesting that increased sodium intake leads to water retention, subsequently elevating hydrostatic pressure on blood vessel walls. Dr. Gupta's team is exploring an alternative hypothesis, investigating whether sodium may incite a proinflammatory response contributing to vascular stiffening.
The average American consumes around 3,400 milligrams of sodium daily, primarily from processed or restaurant food, surpassing the recommended limit of 2,300 milligrams set by the Food and Drug Administration. While advising against discontinuing prescribed medications, the study emphasizes the potential benefits of sodium reduction in conjunction with existing treatments. The challenge lies in encouraging long-term dietary changes, with experts like epidemiologist Bruce Neal suggesting a switch to potassium-supplemented salt as a practical solution. Neal parallels the successful introduction of iodized salt in 1924, illustrating the possibility of a widespread shift towards potassium-supplemented salt for improved cardiovascular health. In the interim, reducing reliance on processed foods and opting for lower-sodium alternatives remain practical measures for individuals seeking to manage their blood pressure through dietary modifications.