Grapes have a long and storied history within the realm of healing, from the grape leaves that were once used to quell pain, inflammation and bleeding to the avowed healing properties of wine. In the more recent past, it has been discovered that many of the healing properties of grapes stem from the polyphenol content of their seeds. Polyphenols are powerful anti-oxidants that neutralize free radicals in your bloodstream. For more information on how free radicals and anti-oxidants work, see How To Understand Anti-Oxidants. Polyphenol antioxidants also naturally increase blood vessel dilation (vasodilation), which increases blood flow and decreases blood pressure. Grape seed extract is exactly what it sounds like--an extract produced from the seeds of grapes--with high levels of polyphenols, particularly one polyphenol known as proanthocyanidin that can lower blood pressure naturally.
Here's what you should know about how to use this extract to manage high blood pressure:
- Grape seed extract is available in capsules, tablets, and tinctures. Look for products that are standardized to 95% OPC content. (OPC is an abbreviation for oligomeric proanthocyanidins, which are a class of flavonoid complexes.)
- In its first human trial, grape seed extract performed well. In results reported in March, 2006, a University of California-Davis study showed that systolic blood pressure (the top number of a blood pressure reading) and diastolic blood pressure (the bottom number of a blood pressure reading) dropped an average of 12 and 8 points respectively, in male and female subjects with metabolic syndrome who took either a 150 or 300 milligram dose of of grape seed extract daily.
- The UC Davis research team recently is currently doing another human trial of grape seed extract using pre-hypertension subjects with a systolic blood pressure of 120-139 mmHg and a diastolic blood pressure of 80-89 mmHg. In animal studies, grape seed extract has reduced blood pressure in pre-hypertensive subjects.
- A study reported in the Journal of Hypertension found that grape seed polyphenols in combination with Vitamin C increased both systolic and diastolic blood pressure. This study suggests caution in combining Vitamin C supplements with grape seed extract.
- Grape seed extract is considered safe. However, because herbs and dietary supplements are not strictly regulated by the U.S. food and Drug Administration, it is difficult to verify the purity and strength of products claiming to contain the extract. Also remember that the extract may interact with other herbs, supplements, or medications. For example, it increase the risk of bleeding. Grape seed extract should only be used with the guidance of a qualified health care professional.
- And while this might seem obvious....if you are allergic to grapes, odds are that you are allergic to grape seed extract and should not take it to reduce high blood pressure or for any other reasons.
In addition to its ability to manage and control blood pressure, grape seed extract has some additional benefits:
- Grape seed extract may also protect against cardiovascular disease by restoring impaired endothelial function and by protecting against the oxidation of low-density lipoprotein (LDL) or the "bad" cholesterol.
Animal studies have suggested that topical grape seed extract promotes antitumor activity. Test tube studies suggest that it inhibits human lung cancer, breast cancer, and gastric adenocarcinoma cells. Human trials of the extract's cancer-fighting properties have not yet been conducted.
- Some animal studies suggest that procyanidins from grape seed may promote hair growth. Expect a human trial soon.
Remember that grape seed extract is not a panacea. If you do decide to use it to manage high blood pressure, you still need to follow your doctor's lifestyle, medication and dietary recommendations for controlling your blood pressure.