Sodium reduction is the key ingredient in dietary treatment of hypertension - a randomized controlled trial on sodium, potassium and nitrate.

Sodium reduction was strongly associated with blood pressure reduction in hypertensive patients.

• The change in systolic BP in the low-sodium groups was -7 mmHg (95% CI -9; -5)
• No change in BP was found in the high-sodium groups
• The association between change in BP and sodium reduction was statistically significant (p < 0.0001)
• Participants received sodium chloride supplementation of 130 mmol/day in the high-sodium condition

Nitrate supplementation via beetroot juice was not associated with a change in blood pressure.

• Beetroot juice provided 13 mmol/day of nitrate
• No significant association was found between nitrate supplementation and change in BP (p = 0.31)
• The intervention lasted one week
• Each active supplement was compared against a matching placebo in a double-blind design

Potassium chloride supplementation was associated with a blood pressure reduction compared to high-potassium groups.

• A BP reduction was found in the low-potassium vs. the high-potassium groups (p = 0.03)
• Potassium chloride supplementation dose was 40 mmol/day in the high-potassium condition
• The effect of potassium was less prominent than the effect of sodium reduction
• The finding was observed over a one-week intervention period

Plasma aldosterone and aldosterone-to-renin ratio (ARR) were associated with the change in blood pressure in the low-sodium groups.

• Plasma aldosterone and ARR were specifically associated with BP change in the low-sodium groups
• The authors suggest measuring ARR might be relevant in a clinical setting to predict the BP effect of sodium reduction
• 24-hour blood samples and urine collections were conducted before and after the intervention
• This finding suggests ARR may identify patients most likely to respond to sodium reduction

The study was a double-blind randomized controlled trial using a factorial design with eight treatment groups.

• 90 participants with hypertension were enrolled and randomized to eight groups
• Groups received different combinations of sodium chloride, potassium chloride, and beetroot juice supplementation or matching placebos
• The intervention lasted one week
• Outcomes included 24-hour blood pressure monitoring, blood samples, and 24-hour urine collection conducted before and after the intervention
• The trial was registered at clinicaltrialsregister.eu with identifier 2021-003407-17