New Findings Show Low-Salt Diet Lowers Systolic Blood Pressure
A low-sodium approach can reduce systolic blood pressure by about 6 mmHg within a week. This observation appeared in a study reported in JAMA and adds to the evidence that dietary choices influence cardiovascular risk.
In the trial, 213 adults aged 50 to 75, some with hypertension and some without, participated. Participants began on their regular diets while blood pressure was monitored. Then they were randomly assigned to follow either a high-sodium or a low-sodium diet for one week. After that phase, they switched to the opposite diet for a second week. Blood pressure was measured at the end of each diet period to assess the effect.
On the baseline regular diet, the average systolic blood pressure was 125 mmHg. When consuming more sodium, average systolic pressure rose to 126 mmHg. Conversely, consuming less sodium lowered this measure to 119 mmHg. All readings were taken on the final day of each dietary period.
Researchers noted that the reduction in blood pressure was statistically meaningful and resembled the effect seen with antihypertensive medications when used alone. This suggests dietary sodium intake can meaningfully influence blood pressure for many people.
The beneficial effect appeared in about three-quarters of participants who had hypertension and were on medications to lower blood pressure. In some individuals, the expected benefits were less pronounced, primarily when adherence to the diet was not strict. Urine tests confirmed that higher sodium intake led to increased sodium excretion, aligning with the dietary changes.
Hypertension remains the most common chronic condition globally, affecting roughly 1.3 billion people and contributing to about one in eight deaths worldwide. While it has long been known that salt intake can affect blood pressure, past studies left gaps, including the inclusion of participants who were already receiving antihypertensive therapy. This research helps fill that gap by showing how diet interacts with medication in real-world settings.
These findings come at a time when cardiovascular risk reduction continues to be a major public health focus in North America. Diet and lifestyle decisions, such as reducing sodium intake, play a central role in managing blood pressure and improving long-term heart health for diverse populations across Canada and the United States. In context, medical professionals encourage individuals to discuss dietary changes with their care providers and to consider sodium intake as part of a comprehensive approach to cardiovascular risk management.
In summary, a low-sodium diet can produce meaningful blood pressure reductions for many people, including those already taking blood pressure–lowering medications. The study emphasizes the value of dietary strategies as part of an integrated plan to improve heart health and reduce the risk of hypertension-related complications.