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Effects of Peppermint Oil in Pre-metabolic Syndrome

Effects of Peppermint Oil in Pre-metabolic Syndrome.

Status
Completed
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07815899
Enrollment
40
Registered
2026-09-11
Start date
2025-01-01
Completion date
2026-09-01
Last updated
2026-09-11

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pre-metabolic Syndrome

Brief summary

Cardiovascular and metabolic diseases are leading causes of morbidity and mortality worldwide; therefore, the development of effective preventive interventions is paramount. Pre-metabolic syndrome, characterised by the presence of cardiometabolic risk factors without meeting the full diagnostic criteria for metabolic syndrome, may represent an important opportunity for early intervention. Dietary interventions are particularly attractive because they may carry fewer risks and impose a lower financial burden than pharmacological treatments. Our previous randomised trial showed that oral peppermint oil supplementation improved systolic blood pressure and selected blood lipid parameters in healthy adults. However, no placebo-controlled randomised trial has examined the effects of peppermint oil supplementation in adults with pre-metabolic syndrome. Therefore, the primary purpose of the proposed investigation is to determine whether oral peppermint oil supplementation improves cardiometabolic parameters in adults with pre-metabolic syndrome.

Interventions

DIETARY_SUPPLEMENTPeppermint Oil

50 uL of peppermint oil, which will be diluted with 100 mL of water - taken twice per day.

RADIATIONPlacebo

Identical in taste and colour to the supplement juice, but with no peppermint content.

Sponsors

University of Central Lancashire
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

Aged 18-65 years. Meet two of the five metabolic syndrome criteria. Not taking prescribed medication specifically intended to manage blood pressure, blood glucose or blood lipids. Able to complete written questionnaires independently. Able to provide informed consent.

Exclusion criteria

Diagnosed diabetes mellitus. Known cardiovascular disease or clinically significant cardiovascular comorbidity, including coronary heart disease, symptomatic heart failure, clinically significant arrhythmia, or a history of stroke or transient ischaemic attack within the previous six months. Known or suspected secondary hypertension, including renal, renovascular or endocrine causes. Known clinically significant renal impairment or severe hepatic disease. Evidence or history of hypertension-related target-organ damage requiring specialist management. Pregnant or lactating. Allergy or known intolerance to peppermint or any ingredient contained in the intervention or placebo. Habitual consumption of peppermint products. Regular consumption of antioxidant or other dietary supplements likely to influence cardiometabolic outcomes. Body mass index greater than 40.0 kg/m². Current enrolment in another clinical trial or use of another intervention or therapy likely to influence the study outcomes. Any condition likely to compromise informed consent, protocol compliance or outcome assessment, including severe psychiatric illness, cognitive impairment, or active substance or alcohol misuse.

Design outcomes

Primary

MeasureTime frameDescription
Systolic blood pressureBaselineSystolic blood pressure - measured using a digital blood pressure monitor

Secondary

MeasureTime frameDescription
Diastolic blood pressureBaselineDiastolic blood pressure - measured using a digital blood pressure monitor
Percent bodyfat and fat massBaselineParticipants percentage composition of fat - measured using bio-electrical impedance
Waist circumferenceBaselineWaist circumference - measured using anthropocentric tape
Waist to hip ratioBaselineRatio of waist to hip circumference - measured using anthropocentric tape
Blood glucoseBaselineCapillary blood glucose - mmol/L
Blood triglyceridesBaselineCapillary blood triglycerides - mmol/L
Blood cholesterol (Total, HDL & LDL)BaselineCapillary blood cholesterol - mmol/L
Total and HDL cholesterol ratioBaselineRatio of total cholesterol to HDL cholesterol
LDL and HDL cholesterol ratioBaselineRatio of LDL to HDL cholesterol
Triglyceride glucose indexBaselineLog transformed measurement of the blood glucose and blood triglyceride measures outlined above.
Coop-Wonka chartBaselinePsychological wellbeing - The Coop-Wonka chart is a six item questionnaire with a 1-5 scoring system for each thus the chart has a maximum score of 30 which indicates the lowest possible psychological Wellbeing.
Beck Depression InventoryBaselinePsychological wellbeing - the Beck Depression Inventory is a 21 questionnaire with questions that range in scoring from 0-3, thus the maximum score is 63 which is the highest depression score possible.
State Trait Anxiety InventoryBaselinePsychological wellbeing - the state trait anxiety inventory is a 40 item questionnaire with each question having a 1-4 score system, thus the maximum score is 80 which indicates the highest level of anxiety.
Pittsburgh Sleep Quality IndexBaselineSleep quality - The Pittsburgh Sleep Quality index, is a questionnaire that consists of 19 self-rated questions, grouped into 7 components. Each component is scored separately, weighted equally on a 0 - 3 scale and the scores of the 7 components are then added to give a global score, which has a range of 0 - 21 with higher scores indicating worse sleep quality.
Epworth Sleepiness ScaleBaselineSleep quality - The Epworth Sleepiness Scale is a self-administered questionnaire with 8 questions. Respondents are asked to rate, on a 4-point scale (0-3) with a maximum score of 24.
Insomnia Severity IndexBaselineSleep quality - The Insomnia Severity Index is a brief instrument designed to assess the severity of both nighttime and daytime components of insomnia. The Insomnia Severity Index is a 7-item self-report questionnaire yielding a total score ranging from 0 to 28.

Countries

United Kingdom

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Sep 12, 2026