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Efficacy of Spearmint Tea in Relieving Osteoarthritis of the Knee

Human Clinical Trial to Investigate the Effects of High Rosmarinic Acid Spearmint Tea on Markers of Pain, Physical Function and Disease Activity in Osteoarthritis of the Knee

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01380015
Enrollment
49
Registered
2011-06-27
Start date
2011-07-31
Completion date
2012-12-31
Last updated
2013-01-23

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

Conditions

Osteoarthritis of the Knee

Keywords

osteoarthritis, spearmint, rosmarinic acid

Brief summary

The purpose of this study is to investigate the benefits of daily consumption of a high rosmarinic acid spearmint tea, developed by the University of Guelph, on measures of pain, physical function and disease activity in osteoarthritis of the knee. The investigators hypothesize that a spearmint tea high in rosmarinic acid is efficacious in mitigating the symptoms of osteoarthritis of the knee through its actions in reducing cartilage degradation, oxidative stress and inflammation.

Detailed description

Healthy adults with a clinical diagnosis of osteoarthritis of the knee will be recruited and will undergo a brief phone screening interview, followed by a detailed in-person screening process, to determine study eligibility. Eligible participants will be matched according to sex, baseline pain according to the Western Ontario and McMaster Universities Arthritis Index (WOMAC) score, and duration of osteoarthritis. Participants will then be randomly assigned to receive either the investigative high rosmarinic acid spearmint tea or a comparable placebo mint tea. During the 4-month treatment period, participants will consume two cups (300 mL in the morning and 300 mL in the evening) of either the high rosmarinic acid spearmint tea (approximately 300 mg rosmarinic acid per day) or the commercial spearmint tea (approximately 20 mg of rosmarinic acid per day) daily. Data collection will occur at baseline (week 0), mid-treatment (week 8), post-treatment (week 16), and follow-up (week 20). Outcome measures include WOMAC and SF-36 scores, physical function (6-minute walk, stair climb task), inflammatory markers (serum C-reactive protein), and self-reported changes in pain medication use. In a sub-set of consenting participants deemed eligible by the study physician, a synovial fluid sample will be drawn from the knee for the analyses of cartilage degradation biomarkers (GAG, COMP, PGE2, NO) at baseline (week 0) and post-treatment (week 16).

Interventions

OTHERCommercially spearmint tea

Commercially available, non-selectively bred spearmint tea.

OTHERHigh Rosmarinic Acid Spearmint Tea

The investigational product will be a high rosmarinic acid spearmint tea (700B) developed by the Department of Plant Agriculture, University of Guelph. Clone 700B has been selectively bred to contain a rosmarinic acid content 15-20 times greater than that of typical mint.

Sponsors

Ontario Ministry of Agriculture, Food and Rural Affairs
CollaboratorOTHER_GOV
University of Guelph
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

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

Inclusion criteria

* Is at least 18 years or older * Have been diagnosed by a health care professional with osteoarthritis of the knee * Demonstrates a WOMAC pain score greater then 125 at time of study screening

Exclusion criteria

* Has any other systemic or rheumatic arthritis * Has completed or is planning to undergo knee replacement surgery * Has had a chemical, radiologic, or surgical synovectomy in any large joint within the previous 3 months * Has any concomitant inflammatory processes such as infectious or rheumatic disease * Has any gastrointestinal ulcers * Has any clinically significant, uncontrolled cardiovascular, hepatic, renal, or any other medical condition that may interfere with the study * Has any serious medication conditions such as recent (within the previous 6 months) heart attack, stroke, cancer and/or diabetes * Has a recent history (within the previous 6 months) of a clinically significant psychiatric disorder other than mild depression * Has a known allergy or hypersensitivity to mint or any other food allergies * Smokes, drinks alcohol (\>14 drinks per week) or participates in recreational drug use * Has participated in a clinical trial involving an investigational or marketed drug within the previous 6 months * Women who are pregnant or plan to become pregnant during the study period, women who have recently (within the previous 6 months) given birth, women who are currently lactating or have only recently (within the previous 6 months) stopped lactating.

Design outcomes

Primary

MeasureTime frameDescription
Self-reported ratings of pain and physical functionFour monthsData collection of self-reported ratings of pain and physical function (WOMAC), self-reported ratings of overall physical and mental health (SF-36), and self-reported changes in the use of concomitant pain and inflammation medications (study diary) will occur at baseline (week 0), mid-treatment (week 8), post-treatment (week 16), and follow-up (week 20).
Use of concomitant pain/inflammatory medications for the management of osteoarthritis symptomsFour months

Secondary

MeasureTime frameDescription
Performance-based measures of physical functionFour monthsData for performance-based assessment of physical function (6-minute walk, stair climb task) will be collected at baseline (week 0), mid-treatment (week 8), post-treatment (week 16), and follow-up (week 20).
Change in synovial fluid biomarkers of cartilage degradationFour monthsIn a sub-set of participants, a synovial fluid sample will be drawn (i.e. arthocentesis) for the analyses of cartilage degradation biomarkers (GAG, COMP, PGE2, NO) at baseline (week 0) and post-treatment (week 16).

Countries

Canada

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 7, 2026