The guarana plant is a climbing plant of Brazil with fruit the size of coffee beans. What is eaten from it is chemically equivalent to caffeine. It is Guarana has been shown to induce apoptosis or cell death in lung cancer cells, to have anti-oxidant properties, to increase cognitive and mental function, to increase energy and help in weight loss!
A 2007 human pilot study assessed acute behavioral effects to four doses (37.5 mg, 75 mg, 150 mg and 300 mg). Memory, alertness and mood were increased by the two lower doses These studies have not been evaluated by the Food and Drug Administration or any similar government agencies. Use of guaran must proceed with caution and with the approval of a physician. For more studies on guarana, look it up on www.pubmed.gov.
Disclaimer: None of the above information can be taken as a substitute for advice from a medical professional, such as a physician.
My third book, Pocket Guide to Fitness, is available on www.louizapatsis.com, http://www.authorhouse.com, www.bn.com and http://www.amazon.com. If you look up my name on those Web sites, you will find my other books The Boy in a Wheelchair and Life, Work and Play: Poems and Short Stories.