Clinical research has shown that High OPC Pine Bark Extract (PBE) may help to improve cardiovascular health through positive effects on:
- Endothelial function
- Plasma viscosity
- Fibrinogen levels
- Systolic blood pressure.
Two key clinical trials have studied the effects of high OPC Pine Bark Extract (PBE) on parameters of cardiovascular health:
Study 1. Pilot evaluation of the clinical, biochemical hematological and hemodynamic effects of flavonoid dietary supplementation in healthy people
This study was carried out by Dr. Brett Shand and Prof. Russell Scott of the Lipid & Diabetes Research Group, Christchurch Hospital, Christchurch, New Zealand. In this trial, 24 healthy subjects, age 55-75, received a daily dose of 480 mg of high OPC PBE and 240 mg vitamin C over 12 weeks. This first formal clinical trial confirmed the safety of High OPC PBE. No adverse events were observed in this study, and no adverse effects were detected on routine laboratory indices of
- glycemic control
- renal function
- liver function
- plasma lipid profile
- hematology
The data indicated that the supplementation was associated with beneficial effects on a range of clinical parameters shown below. (For the full details of this study see the scientific publication by Shand et al., 2003, Phytotherapy Research Vol.17 p490.) The cardiovascular measurements in this study showed improvements in blood flow indicating better endothelial function. The reduction in plasma viscosity indicated lower levels of inflammation in the body. Reduction of systolic blood pressure further confirmed a healthier cardiovascular system after 12 week of supplementation.
Study 2. Double-blind, controlled study on the vascular, anti-inflammatory, antioxidant and anthropometric effects of High OPC PBE in chronic smokers
This study was carried out by Joanna Young, Dr. Brett Shand and Prof. Russell Scott of the Lipid & Diabetes Research Group, Christchurch Hospital, Christchurch, New Zealand. In this trial 44 smokers, aged 40-67, were assigned to a treatment and a control group. For 12 weeks 22 subjects in the treatment group received 480 mg High OPC PBE and 60 mg vitamin C daily, and the 22 control subjects received 60 mg vitamin C only per day. In this second clinical trial High OPC PBE was again very well tolerated with no adverse reactions and normal laboratory measures of all biochemical and haematological parameters. The data indicated that High OPC PBE was associated with beneficial effects on a range of clinical parameters shown below. (For the full details of this study see the scientific publication by Young et al., 2006, Free Radical Research Vol.40 p85.) In this study High OPC PBE reduced plasma fibrinogen levels in heavy smokers. After 12 weeks there was a significant decrease in fibrinogen levels in the High OPC PBE + Vitamin C treatment group in comparison to Vitamin C alone in subjects with a heavier smoking history [p=0.009]. Data expressed as means +/- SEM. Plasma fibrinogen is a well established risk factor of cardiovascular disease and inflammation. Reductions in fibrinogen levels indicate improved cardiovascular and inflammatory status. In Studies 2 and 4 (description of study 4 click here) there were reductions in systolic blood pressure with High OPC PBE. Since, these reductions did not reach statistical significance, both studies were analysed together in a ‘Meta-Analysis’. This type of analysis gives more statistical power and allows to test whether the reduced blood pressure findings were likely to be true. The meta-analysis included the 6 and 12 week time-points of study 2, and included (+ht) or excluded (-ht) subjects on anti-hypertensive medications from study 4. The combined results showed that High OPC PBE supplementation significantly reduced systolic blood pressure whereas Vitamin C did not lead to any reduction.