Low Sodium Diet Helps Blood Pressure in Diabetics

observational-study PMID: 35388704

Quick Summary: A study found that a low-sodium diet, based on the DASH eating plan, helped lower blood pressure in people with both high blood pressure and type 2 diabetes. Both groups saw improvements, but the low-sodium group showed a slightly bigger drop in blood pressure.

Does a Low Sodium Diet Lower Blood Pressure?

Yes! This research shows that reducing sodium intake can significantly lower blood pressure in people with high blood pressure and type 2 diabetes. Following a modified DASH diet, which focuses on fruits, vegetables, and low-sodium foods, can be a helpful strategy.

Study Details

Who was studied: 61 adults with high blood pressure and type 2 diabetes.

How long: The study lasted for 8 weeks.

What they took: Participants were split into two groups. One group used regular salt, and the other used low-sodium salt. Both groups also received guidance on following a DASH diet.

What This Means For You

Lower Blood Pressure: If you have high blood pressure and diabetes, reducing sodium in your diet, like following a DASH diet, could help lower your blood pressure.

Easy Changes: Start by reading food labels and choosing low-sodium options. Cook at home more often so you can control the amount of salt you use.

Talk to Your Doctor: Always discuss any dietary changes with your doctor, especially if you take medications for blood pressure or diabetes.

Study Limitations

Small Study: The study involved a relatively small number of people, so the results might not apply to everyone.

Short Time: The study only lasted 8 weeks. Longer studies are needed to see if the benefits last.

Self-Reporting: The study relied on participants to report what they ate, which can sometimes be inaccurate.

Key Findings

The study demonstrated that sodium reduction based on a modified DASH diet significantly lowered systolic (SBP) and diastolic blood pressure (DBP) in hypertensive patients with type 2 diabetes. The low sodium group experienced greater decreases (SBP: -14.32 mmHg, DBP: -6.32 mmHg) compared to the common salt group (SBP: -10.98 mmHg, DBP: -5.24 mmHg), though between-group differences were not statistically significant (SBP: p = 0.929, DBP: p = 0.093). Sodium intake decreased significantly in the low sodium group, while potassium intake increased, suggesting improved dietary quality. Both interventions were deemed safe and feasible for clinical application.

Study Design

This was an observational study with a quasi-experimental design, involving 61 hypertensive patients with type 2 diabetes recruited from the community. Participants were randomized into two groups: a common salt group (n = 30) and a low sodium salt group (n = 31). The 8-week intervention included three phases: dietary guidance (weeks 1–2), centralized feeding (weeks 3–4), and home-based medical care (weeks 5–8). Blood pressure, salt intake, and medication use were monitored weekly, with physical exams conducted at baseline, week 4, and week 8.

Dosage & Administration

The low sodium group consumed low sodium salt (specific sodium content not quantified in the summary), while the common salt group used regular table salt. The intervention phases included:
1. Dietary guidance: Education on sodium reduction and DASH principles.
2. Centralized feeding: Controlled meals provided for 2 weeks.
3. Home medical care: Self-managed dietary adherence with weekly follow-ups.
No specific dosage metrics for sodium intake were reported in the provided summary.

Results & Efficacy

Low sodium group:
SBP decreased by 14.32 mmHg (p < 0.001).
DBP decreased by 6.32 mmHg (p < 0.001).
Common salt group:
SBP decreased by 10.98 mmHg (p < 0.001).
DBP decreased by 5.24 mmHg (p = 0.001).
Between-group comparisons:
SBP difference: -0.28 mmHg (p = 0.929, not significant).
DBP difference: -3.32 mmHg (p = 0.093, not significant).
Dietary changes: Sodium intake decreased significantly in the low sodium group (p < 0.05), while potassium intake increased (p < 0.05). No such changes were observed in the common salt group.

Limitations

Observational design: Limited causal inference due to lack of randomization and control over confounding variables.
Small sample size: Results may lack generalizability to broader populations.
Short duration: 8-week follow-up may not capture long-term efficacy or safety.
Self-reported adherence: Salt intake and medication use relied on participant reporting, risking bias.
No detailed sodium dosing: Specific sodium quantities consumed were not quantified.
Future research should prioritize randomized controlled trials with larger cohorts, longer follow-ups, and direct sodium intake measurements.

Clinical Relevance

For hypertensive patients with type 2 diabetes, adopting a modified DASH diet with reduced sodium intake can effectively lower blood pressure (-14.32 mmHg SBP and -6.32 mmHg DBP) without adverse effects. While low sodium salt did not outperform common salt statistically, the trend toward greater DBP reduction (-3.32 mmHg) suggests potential benefits of combining sodium restriction with potassium-rich foods. Clinicians should emphasize dietary counseling and home-based adherence strategies, as the intervention succeeded even after centralized feeding ended. However, the lack of significant between-group differences highlights the need for further studies to clarify optimal sodium targets in this population.

Source: PubMed (2022)