Bark Extract

Bark Extract

White Willow Bark, ECA STACK And Weight Loss

The bark of the white willow tree (Salix alba) is a source of salicin and other salicylates compounds similar in structure to aspirin (acetyl-salicylic acid). Native Americans are thought to have used ground willow bark and bark steeped for tea as medicinal remedies for everything from pain to fevers. Today, white willow bark is often used as a natural alternative to aspirin, but perhaps the most common use in dietary supplements is as an adjunct for weight loss (as the A in ECA stacks containing ephedra or synephrine and caffeine in the form of pure caffeine from herbal sources such as guarana or kola nut).

Because of the chemical similarities with aspirin, white willow bark extract is often promoted as an "all natural" alternative but rarely with adequate levels of salicin to impact headaches, inflammation, or fevers.

As a weight loss aid, white willow bark extract offers little to no benefits by itself. In combination with other dietary supplements, however, white willow bark is thought to extend or increase the activity of several thermogenic ingredients (e.g., Citrus aumntium, green tea, guarana, and others) in elevating energy expenditure and promoting fat metabolism.

White willow bark is a common minor ingredient in several weight loss formulations because of the anti-inflammatory properties it derives from inhibiting prostaglandins. A side effect of blocking prostaglandin activity is an inhibition of norepinephrine breakdown; thus, the ultimate effect of white willow bark supplements (when used for weight loss) is to have more norepinephrine around. Norepinephrine is known to interact with a special kind of receptor found on fat cells (fi-3 receptor) to stimulate the breakdown of fat. Because white willow bark appears to increase norepinephrine levels, it might also stimulate fat metabolism, which might lead to enhanced weight loss (Daly et al., 1993; Dulloo and Miller, 1987, 1989; Geissler, 1993; Krieger et al., 1990). Without more definitive findings, however, white willow bark cannot be considered effective on its own as a weight loss agent.

If you have a pounding headache that you want to go away quickly, chances are you will experience better results with regular aspirin from your local pharmacy or grocery store (at a better price than white willow bark). For those looking for a "gentler" approach to either temporary inflammation or weight management (thermogenesis), lower-dose white willow bark might be an effective alternative to aspirin.

The primary active compound in white willow bark is salicin (which can also be found in other plants and herbs such as meadow sweet). In the body, salicin can be converted into salicylic acid, which has powerful effects as an anti-inflammatory and pain reliever. Until synthetic aspirin (acetylsalicylic acid could be produced in large quantities, white willow bark was the treatment of choice for reducing fever, relieving headache and arthritis pain, and controlling swelling, and it remains a popular and approved option in Germany and other European countries (Levesque and Lafont, 2000). Although synthetic aspirin is dearly a more effective pain reliever and anti-inflammatory agent compared with the weaker natural bark extract, white willow bark can also serve as a source of tannins, a combination that might provide a synergistic action in elevating energy expenditure by interfering with the prostaglandin production and inhibiting norepinephrine breakdown (Norton and Meisinger, 1977). This mild effect on keeping norepinephrine concentrations elevated would not be expected to significantly elevate resting energy expenditure on its own, but its effect appears to be enough, when used in combination with other thermogenic supplements, to help promote increased fat oxidation (examples include ma huang (now banned in the United States), synephrine, green tea, guarana, and others).

Stomach ulcers and other gastrointestinal complaints (nausea and diarrhea) are common side effects of prolonged high-dose consumption of either synthetic aspirin or white willow bark extracts. Long-term use of high doses of either salicin source is not recommended, although the natural bark extract is often tolerated much better than the more powerful synthetic aspirin (Toubro et al., 1993). People concerned about blood clotting and bleeding time should use aspirin and white willow bark with caution, because both have the potential to interfere with platelet aggregation and prolong bleeding time (i.e., a blood-thinning effect).

Standardized extracts of white willow bark are available, with total salicin intake typically 60-120 mg per day for relief of acute pain, fever, or inflammation. For longer-term consumption as an adjunct to weight management and thermogenesis, smaller doses are generally tolerated much better (Toubro et al., 1993)