Resveratrol is a polyphenol compound found in some plants, including the skins of dark colored grapes, the source of resveratrol in red wine.
Resveratrol is also found in cranberries or cranberry juice, cacao or dark chocolate and peanuts. But the best source of resveratrol is Japanese or Chinese knotweed, used in supplements. 
The knotweed plant is an aggressive weed that can grow anywhere under hostile conditions. It’s so aggressive that many people don’t want it near them or the agricultural or botanical plants they are trying to grow. Knotweed has been part of Asian medicine for centuries. It came to North America from Asia through Britain.
Researchers and holistic medical practitioners have discovered that resveratrol is a powerful antioxidant and a potential cardiovascular protector and anti-cancer compound; the resveratrol molecule is small enough to cross the blood brain barrier.
That last characteristic has motivated some to employ resveratrol as an adjunct for treating Lyme Disease and has created enough curiosity to explore resveratrol for reducing dementia, Alzheimer’s and other neurological disorders.
While there is a lot of disagreement regarding resveratrol’s ability to create a chain reaction that ultimately destroys “aging genes,” one thing is certain: animal studies have shown that resveratrol increases mitochondrial density and function.
Mitochondria are located in animal and human cells and convert food into adenosine triphosphate (ATP), the energy currency for cellular metabolism and the energy source for organs or muscles comprised of those living cells.
That factor alone would contribute to a healthier life as one ages. Longevity may be a different matter.
Four reasons confirmed by research to consume resveratrol
(1) Neurological and neurovascular effects of resveratrol were sought by researchers in Hamdard University of New Delhi, India, using an animal (mice) study. Their study was published by Brain Research in 2009.
The researchers induced mini-strokes in rats to cause temporary oxygen and blood reduction in their mid-brains. Shortly before and two hours after each induced stroke, one group was administered 10(-7) grams per kilogram of resveratrol while the control group was not treated with resveratrol.
They found the treated group had their mitochondrial glutathione restored rapidly with minimal mitochondrial damage and brain edema (swelling) compared to the control group without resveratrol. 
(2) Stomach cancer protection with resveratrol was looked into by researchers at Zhejiang University in China’s Zhejiang Province. Their study was published by the World Journal of Gastroenterology in 2005.
The researchers injected human gastric primary cancer cells into mice. Small, medium and large doses of resveratrol were injected into the mice near the tumor areas. They observed significant tumor reduction, up to 40%, in all the mice injected with resveratrol according to resveratrol dosage levels.
Normal cells are programmed for apoptosis (cell death) to allow for new cell replacements. Cancer cells are not programmed that way, so they persist and grow. Cancer cell apoptosis kept occurring as treatments continued.
(3) Heart health with resveratrol was investigated by researchers at New York Medical College in Valhalla, NY, and published in 2007 in the American Journal of Physiology.
Under laboratory conditions, the researchers examined the mechanics of how Mediterranean diets with high levels of resveratrol manage to reduce cardiovascular diseases.
They discovered that resveratrol scavenged H2O2 (hydrogen peroxide) and prevented premature, stress-induced cell death among the surfaces of artery inner-walls.
The researchers considered this action, coupled with resveratrol’s anti-inflammatory properties, as the mechanics of resveratrol’s heart health protection. 
(4) Protection from diabetes and diabetic complications was the focus of researchers at the August Cieszkowski University of Agriculture who wished to examine the mechanics of resveratrol’s known diabetes protection.
Their in vivo (rats) experiment revealed that resveratrol “administered to normal rats at the dose 50mg/kg body weight, diminished blood insulin concentrations at 30min, without concomitant changes in glycemia.”
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