Cat's clawUncaria tomentosa

Did you know?

• Cat's claw belongs to the same plant family as coffee and quinine^{[1, 8]}.

• The vine can climb about 30 meters into the forest canopy, hooking itself on with its curved thorns^{[2, 3]}.

• The Asháninka call the vine savéntaro, "powerful plant", from their words for "plant" and "potent"^[2], and their priests gather only vines of one of its two natural chemical types^{[2, 5]}.

• Its stems hold a drinkable, watery sap that people use to quench their thirst^[3]. In Trinidad the vine is known as liane d'eau, "water vine"^[4].

• A vine takes eight years or more to reach harvest size, and when it is cut above the ground rather than pulled up, it grows back^[3].

• Cat's claw is not devil's claw, a different plant native to southern Africa^{[1, 9]}, and in Peru's markets the name "cat's claw" is given to many different plants^[2].

Origins and history

Cat's claw grows in the wet tropical forests of Central and South America, mostly below 1,000 meters, where it scrambles up through the trees on hooked thorns^{[1, 2, 3]}. Its bark and watery sap have been known to the peoples of the Amazon for generations^{[3, 5]}.

In the early 1970s the Austrian Klaus Keplinger organized the first scientific studies of the vine^[6]. His work led to cat's claw extracts sold in Austria and Germany and to a series of US patents on methods of extracting the bark's oxindole alkaloids, the first granted in 1989^{[6, 10]}. By the 1990s the bark was being gathered in large quantities from Peru's forests^[11], and by 1997 more than 50 US supplement makers sold it^[7]. The boom brought a new concern: protecting the wild vines. In 1999 Peru banned the export of raw or only mechanically processed cat's claw unless it came from managed forest areas or plantations, and called for management plans for the harvest^[11]. Harvesters cut the vine above the ground so it can grow back, rather than pulling up the root^[3].

Traditional uses

Clinical studies in people are still few and small^{[7, 9]}, but cat's claw's place in Amazonian tradition is long and well documented.

• A bitter bark tea

  The Asháninka and other Peruvian peoples have traditionally boiled slices of the bark into a bitter tea, taken regularly to stay well.*^{[2, 6, 7]}

• Immune support

  Cat's claw supports healthy immune function.*^{[5, 12]}

• Joint comfort

  Traditionally taken to support joint comfort and flexibility.*^{[6, 7]}

• Digestive comfort

  Supports digestive comfort.*^{[6, 7]}

• Antioxidant compounds

  The bark provides naturally occurring antioxidant compounds.*^{[2, 12]}

Plant compounds

Cat's claw bark contains oxindole alkaloids^{[6, 7]}. The best known are pentacyclic ones, such as mitraphylline, pteropodine, isopteropodine, speciophylline and uncarine F, and tetracyclic ones, such as rhynchophylline^{[2, 6, 7]}. The bark also contains quinovic acid glycosides, proanthocyanidins (such as catechin and epicatechin) and plant sterols^{[2, 6, 12]}. The vine grows in two natural chemical types, one richer in pentacyclic and one in tetracyclic oxindole alkaloids^{[5, 6]}. Asháninka priests can tell the two apart, and how they do it is still unknown to scientists^[5].