Participants will consume two cups of commercial spearmint tea per day (300 mL in the morning and 300 mL in the evening, providing a total of approximately 20 mg of rosmarinic acid per day) for a total of 4 months.

Participants will consume two cups of a high rosmarinic acid spearmint tea per day (300 mL in the morning and 300 mL in the evening, providing a total of approximately 300 mg of rosmarinic acid per day) for a total of 4 months.

Osteoarthritis of the Knee

Commercially available, non-selectively bred spearmint tea.

Commercially 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.

High Rosmarinic Acid Spearmint Tea

University of Guelph

Human Nutraceutical Research Unit, University of Guelph

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

Data 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).

Data 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).

In 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).

Amanda Wright, Ph.D.

Director, HNRU

Ontario Ministry of Agriculture, Food and Rural Affairs

Arm 2 receives 4 weeks of placebo mint tea (consumed twice a day) followed by 4 weeks of washout and then a further 4 weeks of treatment with study mint tea (consumed twice a day).

Arm 1 receives 4 weeks of treatment with mint tea high in rosmarinic acid, consumed twice a day. Treatment is followed by a 4 week wash-out phase. Subjects then enter a 4 week phase of placebo mint tea (low in rosmarinic acid), to be consumed twice a day.

Nasal Polyps

Mint tea high in rosmarininc acid contains 150mg of rosmarinic acid. To be consumed twice a day for 4 weeks. Brewed in 150ml of boiling water and allowed to steep for 10 minutes.

Mint tea high in rosmarinic acid

Mint tea low in rosmarininc acid contains 10mg of rosmarinic acid. To be consumed twice a day for 4 weeks. Brewed in 150ml of boiling water and allowed to steep for 10 minutes.

rosmarinic acid/inflamație

Efficacy of Spearmint Tea in Relieving Osteoarthritis of the Knee

Mint Tea for the Treatment of Nasal Polyps

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