Lowering Sodium Intake Can Reduce Blood Pressure

randomized-controlled-trial PMID: 33709920

Quick Summary: A study found that helping people with high blood pressure make lifestyle changes, like eating less sodium, significantly lowered their blood pressure. This involved a program that encouraged patients to be active in their own care.

How Cutting Sodium Helped Blood Pressure

The study showed that people with high blood pressure who followed a lifestyle program:

Reduced their sodium intake: They ate less salt.

Lowered their systolic blood pressure: This is the top number in your blood pressure reading.

Lowered their diastolic blood pressure: This is the bottom number in your blood pressure reading.

Study Details

Who was studied: 50 adults with high blood pressure.

How long: The study lasted for 4 months.

What they took: The group that lowered their sodium intake followed a "Continuous Care Model" (CCM). This means they got help and support to make healthy lifestyle changes, like eating a heart-healthy diet and being more active.

What This Means For You

If you have high blood pressure, this study suggests that:

Eating less sodium (salt) can help lower your blood pressure.

Working with a healthcare provider to make lifestyle changes can be effective. This includes things like:

Learning about healthy eating
Setting goals for your diet
Getting regular check-ins and support

Study Limitations

It's important to remember:

The study was small: This means the results might not be the same for everyone.

It was a short study: We don't know if the results would last long-term.

Sodium intake was self-reported: People may not always remember exactly what they ate.

Key Findings

The study found that a 4-month lifestyle intervention using a Continuous Care Model (CCM) significantly reduced dietary sodium intake and blood pressure (BP) in hypertensive patients. Mean sodium intake dropped from 3.12±0.79 g/day to 2.42±0.73 g/day (p=0.021), systolic BP decreased from 144.20±13.12 mm Hg to 128.4±13.04 mm Hg (p<0.001), and diastolic BP fell from 89±9.12 mm Hg to 79.4±8.93 mm Hg (p=0.011) in the experimental group. No significant changes were observed in the control group. The authors concluded that CCM-based lifestyle interventions improve adherence to sodium restrictions and BP management in hypertension.

Study Design

This was a two-group randomized controlled trial (RCT) with a pre‒post test design, conducted over 4 months in 50 adults with hypertension (25 per group). The experimental group received CCM-guided lifestyle modifications emphasizing physical activity and a heart-healthy diet, while the control group received standard care. Outcomes included dietary sodium intake (assessed via dietary records) and BP measurements at baseline and post-intervention.

Dosage & Administration

No supplements or medications were administered. The intervention focused on lifestyle modifications through CCM, which included patient education, goal-setting, and regular follow-ups to promote dietary sodium reduction and physical activity. Sodium intake targets aligned with WHO recommendations (<2 g/day), but specific dietary protocols or food substitutions were not detailed in the summary.

Results & Efficacy

Sodium Intake: Decreased by 0.70 g/day in the experimental group (3.12±0.79 to 2.42±0.73; p=0.021).
Systolic BP: Reduced by 15.8 mm Hg (144.20±13.12 to 128.4±13.04; p<0.001).
Diastolic BP: Decreased by 9.6 mm Hg (89±9.12 to 79.4±8.93; p=0.011).
All outcomes showed statistically significant improvements in the experimental group compared to controls. Effect sizes were moderate for sodium intake and large for BP reductions, though exact effect size metrics (e.g., Cohen’s d) were not reported.

Limitations

Small Sample Size: Only 50 participants (25 per group) limit generalizability.
Short Duration: 4-month follow-up may not reflect long-term efficacy.
Self-Reported Data: Sodium intake was measured via dietary records, risking recall bias.
Lack of Demographic Details: Age, gender, or baseline health metrics (e.g., BMI, medication use) were not specified in the summary.
No Blinding: Open-label design could introduce measurement bias.
Future research should include larger, diverse cohorts, longer follow-up, and biomarker validation of sodium intake.

Clinical Relevance

This study supports lifestyle interventions as a critical adjunct to antihypertensive therapy. The CCM approach—engaging patients as active participants in their care—may enhance adherence to sodium restrictions and improve BP control. For hypertensive individuals, integrating structured behavioral support into clinical practice could yield measurable benefits in 4 months. However, the absence of supplement-specific interventions means findings apply to dietary and behavioral strategies rather than sodium supplements. Clinicians should prioritize patient education and continuous support to optimize hypertension management.