HypertensionProBPNCT00107744

Clinical Trial of Protein and Blood Pressure

A study testing Soy protein-milk protein-carbohydrate, Milk protein-carbohydrate-soy protein and Carbohydrate-soy protein-milk protein in people with Hypertension and Hypercholesterolemia, run by Tulane University.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

Search all trials

Trial summary

The purpose of this randomized, double-blind, controlled trial is to examine the effect of soybean protein supplementation on blood pressure in persons with prehypertension or stage-1 hypertension. Read more about this study

Who is it for?: Ages 22 years and olderHealthy volunteers can take part
Conditions the study is for: Hypertension, Hypercholesterolemia
What is being tested?: Soy protein-milk protein-carbohydrate, Milk protein-carbohydrate-soy protein and Carbohydrate-soy protein-milk protein
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 352 participants
Where: No sites listed yet
Study dates: Sep 2003to Apr 2008
Phase: Interventional
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 22 years and older
All sexes
Healthy volunteers accepted
Adult, Older adult

Who may be able to join

Systolic BP of 120 to 159 mm Hg and diastolic BP of 80 to 95 mm Hg (average of 6 measurements at 2 screening visits)
Willing to participate in all aspects of the study

Who cannot join

Consumption of dietary protein greater than or equal to 1.63 grams/kg per day, as determined by two 24-hour dietary recalls
Stage-2 or higher severe hypertension (systolic BP greater than or equal to 160 mm Hg and/or diastolic BP greater than or equal to 95 mm Hg)
Use of antihypertensive medications or medications that affect BP
History of clinical heart disease (e.g., angina/heart attack, coronary revascularization, heart failure, stroke/transient ischemic attack, peripheral arterial disease)
Kidney disease (serum creatinine level greater than or equal to 1.7 mg/dL for men and greater than or equal to 1.5 mg/dL for women)
Current hypercholesterolemia (fasting serum total cholesterol greater than or equal to 240 mg/dL) or use of cholesterol-lowering medications

Show all 21Show fewer

Current diabetes (fasting serum glucose greater than or equal to 126 mg/dL) or use of insulin or oral hypoglycemic agents
Severe obesity (body mass index greater than or equal to 40 kg/m²)
Current use of prescription weight loss medications, underwent weight loss surgery, and/or experienced weight loss greater than 15 pounds within the 6 months prior to study entry
Cancer (except non-melanoma skin cancer) that required treatment during the year prior to study entry
Consumption of more than 14 alcoholic beverages per week
Current participation in another medical study
Consumption of milk or soy protein greater than or equal to the 90th percentile of intake in the U.S. general population
Has another member of the household participating in the study
Study employees or living with study employees
Allergy or intolerance to soy protein or milk protein products
Allergy to aspartame
Plans to move out of the study area (greater than or equal to 50 miles from the study site) and has difficulty coming to the study site
Inability or unwillingness to cooperate during the screening visits
Poor compliance during the screening period (intake of less than 85% of supplements)
Pregnant or plans to become pregnant during the study

About this study

The purpose of this randomized, double-blind, controlled trial is to examine the effect of soybean protein supplementation on blood pressure in persons with prehypertension or stage-1 hypertension.

Read the detailed description

Background: Epidemiologic studies suggest that vegetable protein intake is inversely related to blood pressure.

Objectives: To examine the effect of soybean protein supplementation on blood pressure in persons with prehypertension or stage-1 hypertension

Design: Randomized, double-blind, controlled trial

Study Participants: 350 participants, aged 35-64 years, with an initial untreated systolic blood pressure of 130-159 mmHg and/or diastolic blood pressure of 80-99 mmHg

Intervention: Study participants will be randomly assigned to take 40-grams of isolated soybean protein supplements per day or complex carbohydrate control for 12 weeks.

Outcomes: Blood pressure measurements will be obtained using random-zero sphygmomanometers at baseline and during the trial at weeks 6 and 12. Net changes in systolic and diastolic blood pressure before and after the intervention is the primary outcome.

Conditions: Hypertension, Hypercholesterolemia
Being tested: Soy protein-milk protein-carbohydrate, Milk protein-carbohydrate-soy protein, Carbohydrate-soy protein-milk protein
Keywords: Blood Pressure; Lipids; Dietary Protein
Medical subject headings: Hypertension, Hypercholesterolemia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Soy protein-milk protein-carbohydrateDietary supplement
40 grams of soy protein per day for 8 weeks, 40 grams of milk protein per day for 8 weeks, and 40 grams of carbohydrate per day for 8 weeks
Milk protein-carbohydrate-soy proteinDietary supplement
40 grams of milk protein per day for 8 weeks, 40 grams of carbohydrate per day for 8 weeks, 40 grams of soy protein per day for 8 weeks.
Carbohydrate-soy protein-milk proteinDietary supplement
40 grams of carbohydrate per day for 8 weeks, 40 grams of soy protein per day for 8 weeks, 40 grams of milk protein per day for 8 weeks.

Study groups in NCT00107744
Study group	Role	What they receive
Soy protein-milk protein-carbohydrate	Active comparator	Participants received 40 grams of soy protein daily for 8 weeks, 40 grams of milk protein daily for 8 weeks, and 40 grams of carbohydrate daily for 8 weeks. Receives: Dietary Supplement: Soy protein-milk protein-carbohydrate
Milk protein-carbohydrate-soy protein	Active comparator	Participants received 40 grams of milk protein daily for 8 weeks, 40 grams of carbohydrate daily for 8 weeks, and 40 grams of soy protein daily for 8 weeks. Receives: Dietary Supplement: Milk protein-carbohydrate-soy protein
Carbohydrate-soy protein-milk protein	Active comparator	Participants received 40 grams of complex carbohydrate daily for 8 weeks, 40 grams of soy protein daily for 8 weeks, and 40 grams of milk protein daily for 8 weeks. Receives: Dietary Supplement: Carbohydrate-soy protein-milk protein

What is being measured

The primary outcome is the main question the study is designed to answer.

Change From Baseline in Average Systolic Blood Pressure at 8 Weeks
The change of systolic blood pressure was calculated as the mean of 6 blood pressure values from two 8-week visits minus the mean of 6 values from 2 baseline visits within each intervention phase. At each visit, 3 BP values were measured with a Hawksley random-zero sphygmomanometer by trained and certified observers who were masked to group assignment. BP readings were taken from the right arm with appropriately sized cuffs after the participant had been seated quietly for 5 minutes. The participant was instructed not to eat, smoke, drink alcohol, or exercise for at least 30 minutes before their BP measurements.
Measured: Baseline and 8 Weeks

Secondary outcomes (2)

Change From Baseline in Serum LDL-cholesterol at 8 Weeks
Change in serum LDL-cholesterol was calculated as LDL-cholesterol at 8 weeks minus LDL-cholesterol at baseline. Over-night fasting serum LDL-cholesterol was measured with an enzymatic method.
Measured: Baseline and 8 Weeks
Body Weight at 8 Weeks
Body weight was measured by trained staff using a standard protocol at week 8.
Measured: Baseline and 8 Weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

Sep 2003Apr 2008

First posted8 Apr 2005 (estimated)
Study startSep 2003
Primary completionApr 2008
Study completionApr 2008

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Publications (5)Papers the sponsor has linked to this study.
Other trials for HypertensionStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase N/A
Primary purpose: Prevention
Allocation: Randomised
Intervention model: Crossover
Model description: The trial participants were assigned to take 40 g/d soy protein, milk protein, or carbohydrate supplementation each for 8 weeks in a random order. A 3-week washout period was implemented between the interventions.
Masking: Triple blind
Who is masked: Participant, Investigator, Outcomes assessor
Enrolment: 352 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT00107744
Sponsor's protocol ID: H0330
Other IDs: R01HL068057
Acronym: ProBP
Status last verified: Jun 2018
First submitted: 7 Apr 2005
Last updated: 12 Apr 2023
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: Yes
Individual data sharing: No

Publications

Kearney PM, Whelton M, Reynolds K, Muntner P, Whelton PK, He J. Global burden of hypertension: analysis of worldwide data. Lancet. 2005 Jan 15-21;365(9455):217-23. doi: 10.1016/S0140-6736(05)17741-1.
PubMed 15652604
He J, Wofford MR, Reynolds K, Chen J, Chen CS, Myers L, Minor DL, Elmer PJ, Jones DW, Whelton PK. Effect of dietary protein supplementation on blood pressure: a randomized, controlled trial. Circulation. 2011 Aug 2;124(5):589-95. doi: 10.1161/CIRCULATIONAHA.110.009159. Epub 2011 Jul 18.
PubMed 21768541
Wofford MR, Rebholz CM, Reynolds K, Chen J, Chen CS, Myers L, Xu J, Jones DW, Whelton PK, He J. Effect of soy and milk protein supplementation on serum lipid levels: a randomized controlled trial. Eur J Clin Nutr. 2012 Apr;66(4):419-25. doi: 10.1038/ejcn.2011.168. Epub 2011 Sep 28.
PubMed 21952693
Rebholz CM, Reynolds K, Wofford MR, Chen J, Kelly TN, Mei H, Whelton PK, He J. Effect of soybean protein on novel cardiovascular disease risk factors: a randomized controlled trial. Eur J Clin Nutr. 2013 Jan;67(1):58-63. doi: 10.1038/ejcn.2012.186. Epub 2012 Nov 28.
PubMed 23187956
Sun Y, Zhang R, Tian L, Liu T, Pan Y, Sun X, Huang Z, Fan J, Chen J, Zhang K, Li S, Chen W, Bazzano LA, He J, Bundy JD, Kelly TN, Li C. Associations of plasma inosine with lipid parameters in a biracial community cohort. Clin Nutr. 2025 Dec;55:113-123. doi: 10.1016/j.clnu.2025.10.011. Epub 2025 Oct 29.
PubMed 41202661

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

Official record

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Study at a glance

From the registry record, last updated by the sponsor on 12 Apr 2023. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Clinical Trial of Protein and Blood Pressure
ClinicalTrials.gov ID: NCT00107744
Acronym / sponsor ID: ProBP / H0330
Conditions: Hypertension, Hypercholesterolemia
Keywords: Blood Pressure; Lipids; Dietary Protein
Study type: Interventional
Recruitment status: Completed
Enrolment: 352 participants (actual)
Lead sponsor: Tulane UniversityUniversity, hospital or other
Collaborators: National Heart, Lung, and Blood Institute (NHLBI)
Study start: Sep 2003
Primary completion: Apr 2008 (actual)
Study completion: Apr 2008 (actual)
First posted: 8 Apr 2005 (estimated)
Results: Posted 5 Jul 2018

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

The purpose of this randomized, double-blind, controlled trial is to examine the effect of soybean protein supplementation on blood pressure in persons with prehypertension or stage-1 hypertension.

Detailed description

Background: Epidemiologic studies suggest that vegetable protein intake is inversely related to blood pressure.

Objectives: To examine the effect of soybean protein supplementation on blood pressure in persons with prehypertension or stage-1 hypertension

Design: Randomized, double-blind, controlled trial

Study Participants: 350 participants, aged 35-64 years, with an initial untreated systolic blood pressure of 130-159 mmHg and/or diastolic blood pressure of 80-99 mmHg

Intervention: Study participants will be randomly assigned to take 40-grams of isolated soybean protein supplements per day or complex carbohydrate control for 12 weeks.

Study design

Primary purpose: Prevention
Allocation: Randomised
Intervention model: Crossover
Masking: Triple blind (participant, investigator, outcomes assessor)
Number of arms: 3
Model description: The trial participants were assigned to take 40 g/d soy protein, milk protein, or carbohydrate supplementation each for 8 weeks in a random order. A 3-week washout period was implemented between the interventions.

Arm	Type	Receives
Soy protein-milk protein-carbohydrate	Active comparator	Dietary Supplement: Soy protein-milk protein-carbohydrateParticipants received 40 grams of soy protein daily for 8 weeks, 40 grams of milk protein daily for 8 weeks, and 40 grams of carbohydrate daily for 8 weeks.
Milk protein-carbohydrate-soy protein	Active comparator	Dietary Supplement: Milk protein-carbohydrate-soy proteinParticipants received 40 grams of milk protein daily for 8 weeks, 40 grams of carbohydrate daily for 8 weeks, and 40 grams of soy protein daily for 8 weeks.
Carbohydrate-soy protein-milk protein	Active comparator	Dietary Supplement: Carbohydrate-soy protein-milk proteinParticipants received 40 grams of complex carbohydrate daily for 8 weeks, 40 grams of soy protein daily for 8 weeks, and 40 grams of milk protein daily for 8 weeks.

Who may qualify

Ages: 22 years and older
Sex: All
Healthy volunteers: Accepted
Age groups: Adult, Older adult

Key inclusion criteria (2 listed)

Systolic BP of 120 to 159 mm Hg and diastolic BP of 80 to 95 mm Hg (average of 6 measurements at 2 screening visits)
Willing to participate in all aspects of the study

Key exclusion criteria (21 listed)

Consumption of dietary protein greater than or equal to 1.63 grams/kg per day, as determined by two 24-hour dietary recalls
Stage-2 or higher severe hypertension (systolic BP greater than or equal to 160 mm Hg and/or diastolic BP greater than or equal to 95 mm Hg)
Use of antihypertensive medications or medications that affect BP
History of clinical heart disease (e.g., angina/heart attack, coronary revascularization, heart failure, stroke/transient ischemic attack, peripheral arterial disease)
Kidney disease (serum creatinine level greater than or equal to 1.7 mg/dL for men and greater than or equal to 1.5 mg/dL for women)

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Soy protein-milk protein-carbohydrate40 grams of soy protein per day for 8 weeks, 40 grams of milk protein per day for 8 weeks, and 40 grams of carbohydrate per day for 8 weeks	Dietary supplement	Soy protein-milk protein-carbohydrate
Milk protein-carbohydrate-soy protein40 grams of milk protein per day for 8 weeks, 40 grams of carbohydrate per day for 8 weeks, 40 grams of soy protein per day for 8 weeks.	Dietary supplement	Milk protein-carbohydrate-soy protein
Carbohydrate-soy protein-milk protein40 grams of carbohydrate per day for 8 weeks, 40 grams of soy protein per day for 8 weeks, 40 grams of milk protein per day for 8 weeks.	Dietary supplement	Carbohydrate-soy protein-milk protein

Primary outcome

Change From Baseline in Average Systolic Blood Pressure at 8 Weeks
Time frame: Baseline and 8 Weeks
The change of systolic blood pressure was calculated as the mean of 6 blood pressure values from two 8-week visits minus the mean of 6 values from 2 baseline visits within each intervention phase. At each visit, 3 BP values were measured with a Hawksley random-zero sphygmomanometer by trained and certified observers who were masked to group assignment. BP readings were taken from the right arm with appropriately sized cuffs after the participant had been seated quietly for 5 minutes. The participant was instructed not to eat, smoke, drink alcohol, or exercise for at least 30 minutes before their BP measurements.

2 secondary outcomes

Change From Baseline in Serum LDL-cholesterol at 8 Weeks
Time frame: Baseline and 8 Weeks
Body Weight at 8 Weeks
Time frame: Baseline and 8 Weeks

Results and safety

Results posted to the registry on 5 Jul 2018, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Soy Protein-milk Protein-carbohydrate	117	101
Milk Protein-carbohydrate-soy Protein	117	104
Carbohydrate-soy Protein-milk Protein	118	101

Primary outcome: Change From Baseline in Average Systolic Blood Pressure at 8 Weeks

Time frame: Baseline and 8 Weeks. Mean (95% Confidence Interval). Unit: mmHg

Measure	Soy Protein Supplementation n = 284	Milk Protein Supplementation n = 286	Carbohydrate Supplementation n = 287
Value	-1.5 (-2.4 to -0.6)	-1.8 (-2.7 to -1.0)	0.5 (-0.4 to 1.3)

Population analysed: We conducted analysis according to intention-to-treat principle. All participants with data were included in analysis.

2 secondary outcomes are reported in the full results.

Adverse events

Time frame: Through study completion, an average of 24 weeks. Other adverse events reported at 0% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Soy Protein Supplementation	0 of 352 (0%)	0 of 352 (0%)	0 of 352
Milk Protein Supplementation	0 of 352 (0%)	0 of 352 (0%)	0 of 352
Carbohydrate Supplementation	0 of 352 (0%)	0 of 352 (0%)	0 of 352

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 12 Apr 2023.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Background: PubMed 15652604Kearney PM, Whelton M, Reynolds K, Muntner P, Whelton PK, He J. Global burden of hypertension: analysis of worldwide data. Lancet. 2005 Jan 15-21;365(9455):217-23. doi: 10.1016/S0140-6736(05)17741-1.
Results publication: PubMed 21768541He J, Wofford MR, Reynolds K, Chen J, Chen CS, Myers L, Minor DL, Elmer PJ, Jones DW, Whelton PK. Effect of dietary protein supplementation on blood pressure: a randomized, controlled trial. Circulation. 2011 Aug 2;124(5):589-95. doi: 10.1161/CIRCULATIONAHA.110.009159. Epub 2011 Jul 18.
Results publication: PubMed 21952693Wofford MR, Rebholz CM, Reynolds K, Chen J, Chen CS, Myers L, Xu J, Jones DW, Whelton PK, He J. Effect of soy and milk protein supplementation on serum lipid levels: a randomized controlled trial. Eur J Clin Nutr. 2012 Apr;66(4):419-25. doi: 10.1038/ejcn.2011.168. Epub 2011 Sep 28.
Results publication: PubMed 23187956Rebholz CM, Reynolds K, Wofford MR, Chen J, Kelly TN, Mei H, Whelton PK, He J. Effect of soybean protein on novel cardiovascular disease risk factors: a randomized controlled trial. Eur J Clin Nutr. 2013 Jan;67(1):58-63. doi: 10.1038/ejcn.2012.186. Epub 2012 Nov 28.
Derived from this study: PubMed 41202661Sun Y, Zhang R, Tian L, Liu T, Pan Y, Sun X, Huang Z, Fan J, Chen J, Zhang K, Li S, Chen W, Bazzano LA, He J, Bundy JD, Kelly TN, Li C. Associations of plasma inosine with lipid parameters in a biracial community cohort. Clin Nutr. 2025 Dec;55:113-123. doi: 10.1016/j.clnu.2025.10.011. Epub 2025 Oct 29.
Individual participant dataSharing planned: No

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Active, not recruiting
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Chronic Kidney Disease, Hypertension (HTN)
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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Jiang He, MD, PhD study chair

Tulane University

Questions about this trial

What is this clinical trial studying?

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 21 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 12 Apr 2023. Status can change between updates, so confirm with the study contact before making plans.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

Yes. Results are posted in the registry (first posted 5 Jul 2018). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change From Baseline in Average Systolic Blood Pressure at 8 Weeks (time frame: Baseline and 8 Weeks). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00107744, which also lists 5 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 12 Apr 2023.