Tightens automatically if your blood pressure suggests hypertension.
What does the sodium target mean?
Sodium is an essential electrolyte that regulates fluid balance, nerve transmission, and muscle contraction. However, excess dietary sodium is one of the most significant modifiable risk factors for hypertension (high blood pressure), which is in turn the leading modifiable risk factor for cardiovascular disease and stroke worldwide.
The primary mechanism is osmotic: excess sodium in the bloodstream draws water into the circulation, increasing blood volume and therefore blood pressure. The kidneys excrete excess sodium, but this response varies between individuals, "salt-sensitive" individuals show larger blood pressure rises for a given sodium intake. Sensitivity increases with age, obesity, diabetes, and chronic kidney disease.
The USDA Dietary Guidelines for Americans 2020–2025 recommend less than 2,300 mg of sodium per day for adults, consistent with the Tolerable Upper Intake Level. The American Heart Association's ideal target is 1,500 mg/day for most adults, a goal supported by the DASH-sodium trial, which showed this level produces the greatest blood pressure reductions.
For people with established hypertension, even a 1,000 mg/day reduction in sodium intake is associated with a 5–6 mmHg reduction in systolic blood pressure, an effect comparable to some antihypertensive medications. The calculator reflects this by providing a stricter target when blood pressure readings suggest hypertension.
Reference limits
| Population | Sodium limit (mg/day) | Source |
|---|---|---|
| General healthy adults | < 2,300 | USDA Dietary Guidelines 2020–2025 |
| AHA ideal target | < 1,500 | American Heart Association |
| Adults with hypertension | ≤ 1,500 | ACC/AHA 2017 guideline |
| Chronic kidney disease | ≤ 2,000 (review with nephrologist) | KDIGO guidelines |
When should you see a doctor?
If your blood pressure is consistently above 130/80 mmHg, discuss sodium restriction and other lifestyle modifications with your doctor. People with heart failure may have sodium restrictions as low as 1,000–1,500 mg/day prescribed by their cardiologist. Athletes who lose significant sodium in sweat should not restrict sodium as aggressively as sedentary individuals, their needs are quite different and hyponatraemia during endurance events is a real risk.