ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12626001284358

Ethics application status

Approved

Date submitted

12/10/2026

Date registered

27/10/2026

Date last updated

27/10/2026

Date data sharing statement initially provided

27/10/2026

Date results provided

27/10/2026

Type of registration

Retrospectively registered

Titles & IDs

Public title

An experiment to observe the blood pressure after giving acetic acid capsules to healthy adults

Scientific title

The acute effect of acetic acid ingestion on blood pressure in healthy young adults - a randomised controlled trial

Additional trial identifiers [1]

Nil

Universal Trial Number (UTN)

Trial acronym

Related trial records

Health condition

Health condition(s) studied:

blood pressure

Condition category

Condition code

Cardiovascular

Normal development and function of the cardiovascular system

Intervention/exposure

Study type

Interventional

Description of the intervention or exposure

The intervention is a single oral administration of 800 mg acetic acid, given as twenty 40 mg capsules of acetic acid (Bioglan Apple Cider Vinegar capsules).
The intervention was delivered by a BMedSc(Hons) student investigator, under the supervision of a cardiologist.
It was delivered once, in a procedure room of the Victorian Heart Institute, Clayton, VIC.
The capsules were ingested within 10 minutes, under the direct observation of the student investigator who remained in the room. 600mL still water (Mount Franklin) was provided to assist in swallowing the capsules.

Intervention code [1]

Treatment: Other

Description of the comparator or control

The comparator is twenty placebo capsules, of very similar appearance to the intervention capsules. These are manufactured in-house from empty white gelatin capsules (Nutritional Health Supplements) filled with whey protein isolate powder (Bulk Nutrients, Australia).
The capsules were ingested within 10 minutes, under the direct observation of the student investigator who remained in the room. 600mL still water (Mount Franklin) was provided to assist in swallowing the capsules.

Control group

Active

Outcomes

Primary outcome [1]

Delta systolic blood pressure

Timepoint [1]

Measured once on day of active intervention. Measured once on day of placebo. The order is randomised and blinded.

Secondary outcome [1]

Delta diastolic blood pressure

Timepoint [1]

Measured once on day of active intervention. Measure once on day of placebo. The order is randomised and blinded.

Eligibility

Key inclusion criteria

Healthy volunteers.
Aged 18 years and over.
No history of hypertension and not taking anti-hypertensive medications.

Minimum age

18 Years

Maximum age

No limit

Sex

Both males and females

Healthy volunteers

Yes

Key exclusion criteria

Hypertension.

Study design

Purpose of the study

Prevention

Allocation to intervention

Randomised controlled trial

Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)

Randomisation was performed by a non-blinded investigator (A.J.W.) using the random number generator function of Microsoft Excel to allocate participants to active or placebo arms, and treatment allocation was entered into a RedCAPS database. Other investigators, in particular the BMedSc(Hons) student administering the experiment were blinded to treatment allocation until all participants had completed all aspects of the protocol and the RedCAPS database had been locked.

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Computer-generated random sequence.

Masking / blinding

Blinded (masking used)

Who is / are masked / blinded?

The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes

Intervention assignment

Crossover

Other design features

Phase

Not Applicable

Type of endpoint/s

Efficacy

Statistical methods / analysis

Assumptions::
Significance level p=0.05, two sided.
80% probability for the study to be able to detect the difference.
True difference between intervention and placebo is 5 mmHg.
Standard deviation of the delta BP (within patient) is 6 mmHg.
Such a study will require a sample size of 25 participants.

Recruitment

Recruitment status

Completed

Date of first participant enrolment

Anticipated

Actual

26/07/2023

Date of last participant enrolment

Anticipated

Actual

28/08/2023

Date of last data collection

Anticipated

Actual

5/09/2023

Sample size

Target

Accrual to date

Final

Recruitment in Australia

Recruitment state(s)

VIC

Funding & Sponsors

Funding source category [1]

University

Name [1]

Medical School, Monash University

Address [1]

Country [1]

Australia

Primary sponsor type

University

Name

Monash University

Address

Country

Australia

Secondary sponsor category [1]

None

Name [1]

Address [1]

Country [1]

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

Monash University Human Research Ethics Committee

Ethics committee address [1]

https://www.monash.edu/researchoffice/ethics

Ethics committee country [1]

Australia

Date submitted for ethics approval [1]

31/10/2022

Approval date [1]

01/06/2023

Ethics approval number [1]

36358

Summary

Brief summary

High blood pressure (hypertension) is an enormous global public health problem. The complications of poorly controlled hypertension can include stroke, heart failure, myocardial infarction and renal failure. There is evidence that a diet high in indigestible dietary fibre helps to lower blood pressure. This effect may be because bacteria in the colon ferment the undigested fibre and produce short chain fatty acid byproducts such as acetate, proprionate and butyrate. In 2022 we conducted a randomised study and found that ingestion of lactulose (which reaches the colon undigested) lowered the blood pressure and raised plasma acetate. Next we would like to determine whether plasma acetate is the direct cause of this blood pressure lowering effect. This will be done by directly raising the acetate levels in the blood by asking participants to ingest vinegar tablets (acetic acid) or inert placebo tablets. Acetate is absorbed from the upper gastro-intestinal tract, so this intervention will raise the plasma acetate level without any involvement of the colon. After ingestion of the tablets, we will measure blood pressure in the participants.

Trial website

Trial related presentations / publications

Public notes

Contacts

Principal investigator

Name

A/Prof Anthony White

Address

Victorian Heart Institute, Blackburn Road, Clayton VIC 3168

Country

Australia

Phone

+61 3 7511 1680

Fax

[email protected]

Contact person for public queries

Name

Anthony White

Address

Victorian Heart Institute, Blackburn Road, Clayton VIC 3168

Country

Australia

Phone

+61 3 7511 1111

Fax

[email protected]

Contact person for scientific queries

Name

Anthony White

Address

Victorian Heart Institute, Blackburn Road, Clayton VIC 3168

Country

Australia

Phone

+61 3 7511 1111

Fax

[email protected]

Data sharing statement

Will the study consider sharing individual participant data?

No
No IPD sharing reason/comment: De-identified individual participant data will not be shared. Only aggregate study results and summary data will be made available through publication

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually

Type	Is Peer Reviewed?	DOI	Citations or Other Details	Attachment
Basic results	No			Acetic acid study protocol and results for ANZCTR.docx

Documents added automatically

No additional documents have been identified.

Trial Review

Documents added manually

Documents added automatically