Grape seed extract (Vitis vinifera) is a natural substance available in capsule and tablet form. It is usually sourced from grape seeds provided by wine manufacturers.
Why Do People Use Grape Seed Extract?
Since ancient Greece, various parts of the grape have been used for medicinal purposes. Grape seed extract is purported to help treat the following health problems:
- high blood pressure
- high cholesterol
- poor circulation
- complications due to diabetes
- gastrointestinal disorders
- macular degeneration
Proponents claim that grape seed extract can help protect against cancer. In laboratory studies, scientists have demonstrated that grape seed can help fight free radicals (chemical by-products known to cause DNA damage associated with cancer). However, it is still unclear whether grape seed can lower cancer risk in humans.
Benefits of Grape Seed Extract
Although few trials have examined grape seed extract's effects on specific diseases or conditions, preliminary research suggests that grape seed shows promise in treatment and/or prevention of the following:
1) Diabetes-Related Complications
In a 2009 study of 32 type 2 diabetes patients at high cardiovascular risk, participants took 600 mg of grape seed extract or a placebo every day for four weeks. Study results showed that grape seed extract significantly improved markers of inflammation and glycemia. The study's authors suggest that grape seed extract may have a therapeutic role in decreasing cardiovascular risk.
2) High Blood Pressure
In a 2009 study of subjects with metabolic syndrome, researchers found that four weeks of treatment with grape seed extract lowered both systolic and diastolic blood pressure.
Metabolic syndrome is marked by a cluster of health problems (including excess belly fat, high blood pressure, high cholesterol, insulin resistance, and inflammation) known to raise your risk of heart disease and type 2 diabetes.
Grape seed extract may help delay the development of Alzheimer's disease, according to an animal study published in 2009. In tests on mice, scientists discovered that grape seed extract eased inflammation and prevented the accumulation of substances known to form the brain plaques associated with Alzheimer's disease.
Grape seed extract is generally well-tolerated when taken by mouth. It has been used safely for up to 8 weeks in clinical trials.
If you're considering the use of grape seed extract in treatment or prevention of a condition or disease, make sure to consult your physician first.
Although grape seed is generally considered safe, it may cause adverse effects such as headache, dry or itchy scalp, dizziness, and nausea.
Use of Grape Seed Extract
Kar P, Laight D, Rooprai HK, Shaw KM, Cummings M. "Effects of grape seed extract in Type 2 diabetic subjects at high cardiovascular risk: a double blind randomized placebo controlled trial examining metabolic markers, vascular tone, inflammation, oxidative stress and insulin sensitivity." Diabet Med. 2009 26(5):526-31.
National Center for Complementary and Alternative Medicine. "Grape Seed Extract [NCCAM Herbs at a Glance [link: http://nccam.nih.gov/health/grapeseed/]." NCCAM Publication No. D370. Created March 2007. Updated May 2008.
Sivaprakasapillai B, Edirisinghe I, Randolph J, Steinberg F, Kappagoda T. "Effect of grape seed extract on blood pressure in subjects with the metabolic syndrome." Metabolism. 2009 58(12):1743-6.
Wang YJ, Thomas P, Zhong JH, Bi FF, Kosaraju S, Pollard A, Fenech M, Zhou XF. "Consumption of grape seed extract prevents amyloid-beta deposition and attenuates inflammation in brain of an Alzheimer's disease mouse." Neurotox Res. 2009 15(1):3-14.