White Willow (Salix alba)
White willow bark extract comes from the white willow tree, a member of the Salicaceae family; the tree can grow up to 75 feet tall, and thrives near streams or rivers. White willow grows in diverse regions of the world, ranging from parts of Europe, North America, and Asia.
The bark of the white willow tree is a source of salicin and other salicylates – compounds which are similar in structure to aspirin (acetyl salicylic acid). Native Americans are thought to have used ground willow bark and bark steeped for tea as a medicinal remedy for everything from pain relief to fevers. Today, white willow bark is often used as a natural alternative to aspirin - one of the most common uses in dietary supplements is as an adjunct for weight loss. 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 is thought to extend or increase the activity of several thermogenic ingredients in elevating energy expenditure and promoting fat metabolism.
The active ingredient in white willow is salicin, which the body converts into salicylic acid. The first aspirin (acetylsalicylic acid) was made from a different salicin-containing herb--meadowsweet--but works in essentially the same way. All aspirin is now chemically synthesized. It's not surprising, then, that white willow bark is often called "herbal aspirin." The salicylic acid in white willow bark lowers the body's levels of prostaglandins, hormonelike compounds that can cause aches, pain, and inflammation. While white willow bark takes longer to begin acting than aspirin, its effect may last longer. And, unlike aspirin, it doesn't cause stomach bleeding or other known adverse effects.
The primary chemical constituents of White Willow Bark include glycosides (salicin, salicoside), salicortine, tannin, catechin, and flavonoids. Female Willow buds contain phytoestrogens. Salicylic acid is a weak anti-inflammatory agent, but is converted by the liver to acetyl-salicylic acid. The acetylated version has aspirin's more effective anti-inflammatory activity without its gastrointestinal toxicity. The salicylates inhibit the activity of the cyclo-oxgenase enzymes, and thus inhibit the production of prostaglandins and other inflammatory molecules. The excretion of salicylic acid in the urine helps soothe an irritated urinary tract. Willow Bark has long been used for fevers and inflammations. In addition, the astringency of the glycosides makes Willow Bark useful as an antiseptic and astringent. Extracts and infusions of the bark have been used for cleansing the scalp and skin, for treating dandruff, and for treating corns and growths. As a flower essence, this herb reduces bitterness and resentment, and helps those who tend to blame others. Only Black Willow is an anaphrodisiac, while all species are a mild antiseptic. Known topical applications of White Willow Bark include its use as a mouthwash for sore gums, gargle for tonsillitis, hair rinse for dandruff, compress & poultice for burns, insect bites & wounds, and foot soak for sweaty feet. Willow is also an excellent material for making baskets and dowsing rods. The common name Willow includes the species Salix nigra (Black Willow), Salix fragilis, (Crack Willow) and Salix cinerea, which are used interchangeably with Salix alba (White Willow).