A lot has been said already about resveratrol and its promising health benefits. But what about resveratrol supplements, should we take them?
Officially, scientists involved in studying this compound say we should wait until FDA approves a resveratrol pill, which is already in development by big pharma; that figures.
However, some researches have admitted to supplementing with resveratrol, and putting their elderly parents on red wine extract supplements. What should we do?
ConsumerLab.com (requires registration) has recently published a very detail and informative article on this subject. Here it is:
What is Resveratrol?
“Resveratrol is a plant chemical found in red grape skins and grape seeds, purple grape juice and red wine, and in smaller amounts in peanuts.
Resveratrol is also found in other plants such as the roots of the Chinese medicinal herb, hu zhang (Polygonum cuspidatum) – commonly known as Japanese knotweed – which is often the source of resveratrol in supplements. Resveratrol is also found in the roots of a South American shrub (Senna quinquangulata).
Red wine extract, red grape skin extract, grape seed extract (GSE), grape pomace extract (GPE), and Polygonum cuspidatum extract contain varying amounts of resveratrol along with other plant chemicals.
Resveratrol exists in two forms, cis-resveratrol and trans-resveratrol. These forms contain the same type and number of atoms, but the orientation of the atoms is slightly different. Cis- and trans-resveratrol have some biological activities in common while other activities are specific to only one form or the other.
Trans-resveratrol is commercially available and has been the subject of more research than cis-resveratrol – although not all research has adequately established or identified the form used.
What It Does:
The promotion of resveratrol far exceeds it’s base of clinical research. In fact, no human studies evaluating the potential benefits or risks of resveratrol supplements have been reported. However, animal research of resveratrol has demonstrated anti-aging and athletic endurance-enhancing activities.
Test tube experiments with resveratrol have demonstrated antioxidant, anti-inflammatory, anticancer, antiplatelet, cholesterol-lowering, and mild estrogenic activities. Despite the lack of human studies, resveratrol has been promoted for a wide range of uses including the prevention of heart disease and cancer and improving cholesterol levels.
Based on unconfirmed theories, resveratrol has also been proposed as an inhaled treatment for some lung disorders and for prevention and treatment of HIV infection.
How It’s Sold:
The Food and Drug Administration (FDA) has rejected requests by several companies to market supplements labeled to contain resveratrol.
According to the FDA, resveratrol is not a dietary supplement ingredient because it was not marketed prior to enactment of the Dietary Supplement Health & Education Act in 1994 and does not have adequate evidence of safety in humans. Resveratrol has, however, been given investigational new drug status so that it may be tested in clinical studies.
Despite the FDA’s stance, some companies market supplements labeled to contain resveratrol. Others, in an effort to stay within the law, sell “resveratrol” products labeled, for example, as red wine extract, grape skin extract (GSE) grape pomace extract (GPE), or Polygonum cuspidatum extract.
Some products refer to “resveratrol complexes” or “resveratrol formulas,” again without indicating the actual amount of resveratrol contained. Supplements tend to offer anywhere from about 1 milligram to 100 milligrams of resveratrol per day. (For reference, one bottle of red wine has only 1 milligram of resveratrol).
Be aware that some products label their resveratrol in micrograms (Âµg) rather than milligrams (mg). This can make the amount look large, but it takes 1,000 micrograms to equal 1 milligram. For a product that promises 20 Âµg per pill, you would need to take 1,000 pills to get a 20 mg dose.
The Right Dose:
No one knows the right dose of resveratrol that is beneficial and safe for people. Positive studies on mice used daily doses ranging from 22 mg to 400 mg of resveratrol per kilogram of body weight.
In humans, this would be equal to a daily dose of about 1,500 to 28,000 mg of resveratrol, which is far more than that provided by most supplements. Even a leading resveratrol researcher, Dr. David Sinclair at Harvard Medical School, is noted as taking a lower dose: 5 mg per kilogram – about 150 mg per day for the average adult.
Apparently he and other individuals whom he knows that take resveratrol have not reported adverse effects.
Concerns and Cautions:
Although adverse effects of resveratrol in people have not been reported, its safety has not been well evaluated. Short-term studies in healthy animals have shown side effects only at extremely high doses (over 300 mg per kilogram). Long-term side effects are not known.
Resveratrol has mild estrogenic activity that has not been evaluated in humans. Until more is known, women with estrogen-sensitive conditions, including some cancers, are advised to consult a physician before taking resveratrol.
Particularly due to potential anti-growth factor properties, resveratrol should not be used by children nor by woman who are pregnant, nursing or trying to conceive.
Resveratrol reduces the activity of enzymes involved with drug metabolism. Whether resveratrol interferes with drug therapies in humans has not been studied and individuals taking prescription medications are advised to consult a physician before taking resveratrol because of potential drug interactions.
Because resveratrol demonstrates antiplatelet (blood-thinning) activity, individuals taking blood thinners are strongly advised to consult a physician before taking resveratrol because of potential drug interactions.
The Bottom Line:
Although animal studies have shown tantalizing effects with resveratrol, it is too early to know whether it is beneficial to people, what dose is best, and what side effects or even toxicities may occur.
It’s also not clear what’s really in many of these supplements and if they are free of impurities. When other types of supplements have first rocketed into public view, ConsumerLab.com has often found that many do not contain their listed ingredients.
To help shed light on the quality of resveratrol supplements, ConsumerLab.com will be testing products sold in the U.S. and Canada and reporting what it finds in early 2007. Stay tuned.”