Sodium Intake Timing for High Blood Pressure

Overseen By David Pollock, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Alabama at Birmingham

Must not be taking: Antidepressants, Sleep medications

Disqualifiers: Kidney disease, Elevated BP, Diabetes, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

Duration: 9 days

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether the timing of salt intake affects blood pressure and metabolism in people with obesity. Participants will follow a specific diet and take extra salt (oral sodium supplementation) either with breakfast or dinner to observe its impact on blood pressure patterns and overall health. The trial aims to determine if avoiding high salt intake before sleep can improve both blood pressure and metabolic health. Suitable candidates are individuals who are obese but do not have severe kidney issues or uncontrolled high blood pressure. As an unphased trial, this study offers participants the chance to contribute to important research that could lead to better health recommendations for people with obesity.

Will I have to stop taking my current medications?

If you are taking two or more blood pressure medications or supplements regularly, you may not be eligible for the trial. The protocol does not specify if you need to stop other medications, but it seems focused on limiting certain medications.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

Research shows that salt intake can affect blood pressure. Studies have found that consuming high salt levels later in the day can raise blood pressure and increase the risk of heart disease. However, the effect on blood pressure varies based on the timing of salt consumption and overall health.

For those who consume less salt earlier in the day, research suggests that reducing salt intake can lower blood pressure by about 8 mm Hg within a week. This change typically occurs with minimal side effects, indicating most people tolerate it well.

In general, while high salt intake is linked to higher blood pressure, there isn't strong evidence of major side effects from altering the timing of salt consumption for healthy individuals. Consulting a healthcare provider is advisable for any concerns about joining a clinical trial. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it explores how the timing of sodium intake affects high blood pressure, a new angle compared to standard treatments like diuretics and ACE inhibitors. This approach is unique because it doesn't just limit sodium intake; it examines when sodium is consumed, potentially offering a simpler lifestyle adjustment. The trial includes two distinct methods: taking sodium with dinner (Late Sodium) and with breakfast (Early Sodium), which could provide insights into how meal timing influences blood pressure management. This research could lead to more personalized recommendations for people with hypertension, enhancing the effectiveness of dietary interventions alongside traditional medications.

What evidence suggests that the timing of sodium intake could be effective for managing high blood pressure?

Research has shown that eating less salt can help lower blood pressure. One study found that reducing salt intake lowered the top number in a blood pressure reading by about 1.7 points in healthy people. Another study showed that eating less salt for just one week lowered this number by 8 points. The time of day salt is consumed might also matter. Eating a lot of salt in the evening could affect blood pressure patterns and heart health. This trial will compare the effects of consuming sodium at different times of the day. Participants in one arm will take sodium with dinner (Late Sodium), while those in another arm will take sodium with breakfast (Early Sodium), to determine how timing affects blood pressure and health in people with obesity. ^{1 2 3 4 6}

Are You a Good Fit for This Trial?

This trial is for obese African Americans aged 25-45 with a BMI of 30-50. It's not suitable for those with drug/alcohol abuse history, high alcohol consumption, pregnancy, hormone therapy use, sleep medication or antidepressant users, kidney disease sufferers, very high blood pressure individuals (>150/90 mmHg), shift workers, sleep disorder patients (like apnea), major chronic diseases like diabetes or severe anemia.

Inclusion Criteria

My BMI is between 30 and 50.

I am between 25 and 45 years old.

I am between 25 and 45 years old.

Exclusion Criteria

You have a serious mental illness, as determined by a specific evaluation form.

My kidney function is reduced or I have abnormal urine test results.

You have smoked or used tobacco products in the last year.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Run-in Period

Participants consume a standardized diet providing 2.3 g of sodium per day for 7 days

1 week

Treatment

Participants continue the standardized diet for 9 days with additional sodium intake either with dinner or breakfast

9 days

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Oral sodium supplementation

Trial Overview The study tests if the timing of salt intake affects blood pressure rhythms and urinary sodium excretion in obese people. Participants will limit salt before bedtime to see if it improves day-night blood pressure differences and metabolic risk factors by influencing circadian clock factors linked to renal sodium handling.

How Is the Trial Designed?

Group I: Late Sodium Experimental Treatment 1 Intervention

Late sodium load: participants will consume a standardized diet providing 2.3 g of sodium per day for 7 days (run-in period), after which they will continue to consume the standardized diet for the next 9 days and in addition will take 2 g of sodium with dinner each day.

Group II: Early Sodium Experimental Treatment 1 Intervention

Early sodium load: participants will consume a standardized diet providing 2.3 g of sodium per day for 7 days (run-in period), after which they will continue to consume the standardized diet for 9 days and in addition will take 2 g of sodium in the form of salt tablets with breakfast each day.

Oral sodium supplementation is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Sodium supplements for:

• Sodium deficiency
• Hyponatremia

Approved in European Union as Oral sodium for:

• Sodium deficiency
• Hyponatremia
• Dehydration

Approved in Canada as Sodium supplements for:

• Sodium deficiency
• Hyponatremia

Who Is Running the Clinical Trial?

University of Alabama at Birmingham

Lead Sponsor

Trials

1,677

Recruited

2,458,000+

Published Research Related to This Trial

A 10-week study involving 17 elderly hypertensive subjects showed that a reduction in dietary sodium intake by 80 mmol/day led to a significant decrease in clinic supine systolic blood pressure (SBP).

While moderate sodium restriction was beneficial for some individuals, the overall effect on 24-hour blood pressure was not significant, suggesting that this dietary change may not be effective for all elderly hypertensive patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effects of moderate sodium restriction on clinic and twenty-four-hour ambulatory blood pressure in elderly hypertensive subjects. Fotherby, MD., Potter, JF.[2019]

Substantial reductions in sodium intake (75 to 100 mmol/d) can lead to modest decreases in blood pressure, with average reductions of about 1 mmHg for diastolic and 3 to 5 mmHg for systolic pressure, based on clinical trial data.

Current evidence does not support routine dietary sodium restriction for either normotensive or hypertensive individuals, as studies show inconsistent results regarding sodium intake's impact on cardiovascular health outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary sodium and cardiovascular health in hypertensive patients: the case against universal sodium restriction. Alderman, MH.[2019]

Extreme changes in sodium intake can affect blood pressure in both people with normal blood pressure and those with high blood pressure, but the evidence is not strong enough to recommend a general reduction in sodium intake for everyone to prevent hypertension.

Studies show mixed results on the effectiveness of sodium restriction for managing hypertension, and many patients are unlikely to stick to a low-sodium diet without significant support, suggesting that low-sodium diets should not be the primary public health recommendation for treating high blood pressure.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sodium manipulation in the management of hypertension. The view against its general use. Logan, AG.[2019]

A study involving 201 normotensive volunteers and 60 untreated hypertensive patients found that a high sodium diet significantly increased blood pressure, with an average rise of 4.5 mmHg in normotensive individuals and 8.4 mmHg in hypertensive individuals.

The results suggest that reducing sodium intake from 200 to 70 mmol/day could lower blood pressure levels in the general population, potentially decreasing the need for medication in those with hypertension.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of sodium intake on the blood pressure related to age and sex. Myers, J., Morgan, T.[2019]

Multiple guidelines from reputable health organizations over the past decade consistently support sodium restriction as an effective strategy for controlling blood pressure.

These guidelines, including those from the American Heart Association and the World Health Organization, emphasize that reducing sodium intake is both feasible and beneficial for overall cardiovascular health.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Reduction of sodium intake is a prerequisite for preventing and curing high blood pressure in hypertensive patients - second part: guidelines. De Santo, NG.[2019]

In a study of 149 healthy children, restricting dietary sodium intake to 60 mEq/day for 3 months led to a significant decrease in sodium excretion and a small but notable reduction in diastolic blood pressure, indicating that sodium restriction can have a measurable impact on blood pressure in children.

In a separate analysis of 31 children, potassium supplementation resulted in a significant decrease in systolic blood pressure, suggesting that potassium may play a beneficial role in managing blood pressure, although the effects of sodium restriction and potassium supplementation differ.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Blood pressure response to sodium restriction and potassium supplementation in healthy normotensive children. Miller, JZ., Weinberger, MH.[2019]

In a study of 108 participants, reducing dietary sodium intake from 140 to 60 mmol/d while maintaining a high potassium diet led to a significant decrease in home systolic blood pressure by 2.5 mm Hg, indicating that lower sodium can effectively help manage blood pressure.

The study demonstrated that a low sodium diet (50 mmol/d) combined with high potassium intake (over 80 mmol/d) not only reduced urinary sodium levels but also increased urinary potassium, suggesting that this dietary approach could be beneficial for blood pressure control in the general population.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Decreasing dietary sodium while following a self-selected potassium-rich diet reduces blood pressure. Nowson, CA., Morgan, TO., Gibbons, C.[2018]

Dietary salt significantly impacts blood pressure, making sodium intake a key focus in lifestyle modifications for managing hypertension, but recommendations are complicated by varying study results.

Recent major trials show stronger links between sodium intake and blood pressure than earlier studies, yet methodological limitations in measuring sodium intake and other factors make it challenging to establish clear guidelines for sodium consumption.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dietary salt restriction and blood pressure in clinical trials. Lackland, DT., Egan, BM.[2019]

The Satter House Trial of Reduced Sodium Meals (SOTRUE) showed that a low sodium meal plan for 14 days in older adults led to a reduction in seated systolic blood pressure (SBP) from 123 to 112 mmHg, indicating potential benefits for blood pressure management.

While the low sodium diet did lower SBP by 4.8 mmHg compared to a typical sodium diet, the results were not statistically significant, suggesting that further research with a larger sample size and longer duration is necessary to confirm the efficacy and safety of low sodium meals in older adults.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Effects of a Low Sodium Meal Plan on Blood Pressure in Older Adults: The SOTRUE Randomized Feasibility Trial. Juraschek, SP., Millar, CL., Foley, A., et al.[2021]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6770596/

Sodium Intake and Hypertension - PMC - PubMed Central - NIH A large meta-analysis [9] showed that modest reduction in salt intake for four or more weeks causes a significant fall in BP in both hypertensive and ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10640704/

Effect of Dietary Sodium on Blood Pressure 1 week of a low-sodium diet resulted in an average 8–mm Hg reduction in systolic blood pressure vs a high-sodium diet, with few adverse events.

3. nejm.org nejm.org/doi/full/10.1056/NEJM200101043440101

Effects on Blood Pressure of Reduced Dietary Sodium and ... Results. Reducing the sodium intake from the high to the intermediate level reduced the systolic blood pressure by 2.1 mm Hg (P<0.001) during ...

4. ahajournals.org ahajournals.org/doi/10.1161/hypertensionaha.109.131235

Effects of Dietary Sodium Reduction on Blood Pressure in ... Observational studies of large unselected cohorts indicate a positive correlation between dietary salt intake and BP.

5. ahajournals.org ahajournals.org/doi/10.1161/hypertensionaha.113.01034

Reproducibility of Blood Pressure Responses to Dietary ... These data indicate that blood pressure responses to dietary sodium and potassium interventions have long-term reproducibility and stable characteristics in ...

6. clinicaltrials.gov clinicaltrials.gov/ct2/show/NCT01334138

Effect of Dietary Sodium Intake on Blood Pressure in ... The aims of the present study is to determine if the overconsumption of salt influences the bp in patients with uncontrolled hypertension or ...