Guarana is a creeping shrub native to the Amazon, most particularly the regions of Manaus and Parintins. In the Brazilian Amazon where is originated, it often reaches 40 feet in height. The fruit is small, round and bright red in color and grows in clusters. As it ripens the fruit splits and a black seed emerges, giving it the appearance of a eye which the Indians tell legends about. The uses of this medicinal plant by the Amerindians pre-dates the discovery of Brazil. The South American Indian tribes, especially the Guaranis, from whence the name is derived, dry and roast the seeds and mix it into a paste with water. It is then used much the same way as chocolate by the Indians who use it prepare various foods, drinks and medicines. The Rainforest tribes have used guarana mainly as a stimulant, astringent and in treating chronic diarrhea.(1) Throughout the centuries the many secrets and benefits of Guarana were passed on to the settlers. European researchers began studying Guarana in France in Germany in the 1940's finding that the Indians' uses to cure fevers, headaches and cramps and as an energy tonic were well founded. Botanist James Duke cites past and present tribal use in the Rainforest as a preventative for arteriosclerosis, an effective cardiovascular drug, analgesic, astringent, febrifuge, stimulant and tonic used to treat diarrhea, hypertension, migraine, neuralgia, and dysentery.(2) Today the plant is known and used worldwide including as the main ingredient in the "national beverage" of Brazil, "Guarana Soda." Eighty percent of the world's commercial production of Guarana paste is in the middle of the Amazon rainforest in northern Brazil, still performed the Guaranis Indians who wild harvest the seeds and process them into paste by hand. The Brazilian government has become aware of the importance of the local production of Guarana by traditional methods employed by indigenous inhabitants of the rainforest. FUNAI (National Indian Foundation) has set up a number of projects since 1980 to improve the local production of Guarana. Now under the direction of the FUNAI regional authority in Manaus there are many co-operatives in the rainforest which support indigenous tribal economies.(3) The first chemical examination on the Guarana seeds was performed by the German botanist Theodore von Martius who isolated a bitter, white crystalline substance with a remarkable physiological action in the 1700's. This substance was named Guaranine, and was later renamed as Caffeine. Guarana seeds contain up to five percent caffeine (25,000 to 75,000 ppm), as well as trace amounts of Theophylline (500-750 ppm) and Theobromine (300-500 ppm). It also contains large quantities of tannins, starch, a saponin and resinous substances. Guarana is used and well known for its stimulant and thermogenic action. In America today, Guarana is reputed to increase mental alertness and fight fatigue (4) and also to increase stamina and physical endurance.(5) Presently guarana is taken daily as a health tonic by millions of Brazilians who believe is helps overcome heat fatigue, combats premature aging, detoxifies the blood and useful for flatulence, obesity, dyspepsia, fatigue and for arteriosclerosis.(6) In body care products, Guarana has been used for its tonifying and astringent properties. t has been used in the treatment of cellulite due to its lipolytic and vasodilation action. Guarana has been used as an ingredient in shampoos for oily hair and as a coadjutant in hair loss treatments. While the Indians have been using Guarana for centuries, western science has been slowly but surely proving that the indigenous uses are well grounded in science. In 1989 a US patent was filed on a Guarana seed extract which was capable of inhibiting platelet aggregation in mammalian blood. The patent described Guarana's ability to prevent the formation of blood clots and to help in the breakdown of clots that had already been formed.(6) Clinical evidence was presented in conjunction with the patent in 1989 and again in 1991 by a Brazilian research group demonstrating this anti-aggregation properties. Therefore once again, scientific validation is given to a plant used for centuries by the Indians as a heart tonic and to "thin the blood." The use of Guarana as an effective energy tonic and for mental acuity and long-term memory was just recently validated by scientists. In a 1997 study, Guarana increased physical activity of rats as well as increased physical endurance under stress and in increased memory with single doses as well as with chronic doses. Interestingly enough, the study revealed that a whole Guarana seed extract performed better and more effectively than did a comparable dosage of caffeine or Ginseng extract.(10) Another Brazilian research group has been studying Guarana's apparent effect of increasing memory which is thought to be linked to the essential oils found in the seed.(13) Its antibacterial properties against E. coli and Salmonella have been documented as well.