Nettle Root Extract (3,4-divanillyltetrahydrofuran)

<body><h1>Nettle Root Extract</h1>  syn. Urtica Dioica  syn. 3,4-divanillyltetrahydrofuran <div id=’imgblock’><img data-pointer=’9119’/></div> <h2>  Description: </h2>  Stinging nettle (urtica dioica) is an herbal plant found in many warmer parts of Europe, North America, Asia, and Africa. One of the plant’s most known physical characteristics is the presence of fine hairs that produce strong pain and irritation upon contact with the skin. The plant actually derives its Latin name from the word for burn (urere). The stinging nettle plant itself is not poisonous, and its leaves are used to make a variety of food products. Stinging nettle leaves and roots also have a long history of use in traditional (natural) medicine, dating back many centuries. It has been used as a diuretic, a laxative, an analgesic, a wound salve, and to treat numerous conditions including arthritis, ulcers, asthma, and diabetes. <div id=’imgblock’><img data-pointer=’7843’/></div>  Modern studies support many of the traditional uses for nettle leaf and root extracts, suggesting they may offer benefits with ailments such as allergies, sinusitis, benign prostate hypertrophy, arthritis, rheumatism, inflammation, high blood pressure, and even hair loss.474 Of interest to athletic individuals is a property of one of the lignans (3,4-divanillyltetrahydrofuran) found in the roots. It has displayed an extremely high affinity for binding with sex hormone binding globulin (SHBG), a protein that attaches to testosterone and other sex steroids, preventing them from exerting many activities. If this can occur at a significant level in the body with nettle root extract supplementation, it may allow for a higher percentage of free (bioactive) testosterone. While empirical evidence seems to support the use of nettle root extract as a sports nutrition product, further research is needed to validate its potential ergogenic activity in a clinical setting. <h2>  Promoted Benefits:</h2>  Nettle root extract is promoted to block SHBG, increase free testosterone levels, and support the anabolic effects of this hormone. <h2>  Clinical Studies: </h2>  The use of nettle root extract as a sport supplement is only supported by in-vitro clinical studies. Its Clinical Support Rating is 1 (1/ 5)  One such study used test tube experiments to examine the binding of six lignans from the stinging nettle root to SHBG.475 Five of these lignans (neoolivil, secoisolariciresinol, dehydrodiconiferyl alcohol, isolariciresinol, and 3,4-divanillyltetrahydrofuran) were shown to bind the SHBG protein. The lignan 3,4-divanillyltetrahydrofuran bound SHBG with especially high affinity. Many nettle root extracts are now standardized for this lignan as a result of this data. The researchers also reported SHBG binding activity in two of the most common intestinal metabolites of plant lignans (enterodiol and enterolactone), though their binding was not as pronounced as 3,4-divanillyltetrahydrofuran.  There was a large placebo-controlled study (620 subjects) that examined the effect of nettle root extract in patients with benign prostate hyperplasia, which included measurements of the testosterone level.476 The study used a dosage of 360 mg/day, which was taken for six months before hormone levels were assayed. The supplementation of nettle root extract did not result in any change in testosterone level compared to placebo. Unfortunately the measure of free testosterone was not taken, so it is unknown if there was a substantial change in the fraction of bioactive testosterone.  Further research is needed to verify if there is ergogenic value to the use of nettle root extract by athletic individuals. <h2>  Empirical Evidence: </h2>  Nettle root extract is widely available as a stand-alone nutritional supplement. The feedback on this extract for sports nutrition use has been positive, especially with the use of extracts that are standardized for 3,4- divanillyltetrahydrofuran. The primary application in this context is the elevation of endogenous free testosterone levels, and an increase of its anabolic activity. Most users taking these extracts report subjective feelings of elevated androgenicity, and outward signs that the extract is providing the desired effect (oily skin, acne, increased strength). Although there is a lack of substantial clinical support, nettle root extracts do seem to be well regarded among bodybuilders and strength athletes. As with all supplements, a small percentage of users do fail to notice positive effects. Whether this is the result of varying extract potencies, different contexts in which nettle root may impart an ergogenic effect, or individual insensitivity to 3,4-divanillyltetrahydrofuran remains unclear. Nettle root extract (standardized for 3,4-divanillyltetrahydrofuran) has an Empirical Evidence Rating of 5 (5/5).<h2> </h2><h2>  Effective Dosage: </h2>  An effective dosage has not been established. Extracts of varying potencies, and even purified 3,4-divanillyltetrahydrofuran, are available on the sports nutrition market, making dosing difficult to estimate. Manufacturers of standard nettle root extracts commonly recommend 500-1,000 mg per day. <h2>  Side Effects / Safety: </h2>  Nettle root extract has been well tolerated during clinical studies, with no significant side effects. </body>