Guarana, a natural herb imported from Brazil, has been used for centuries by indigenous people of the Amazon as an energizer. Guarana is used primarily in the same manner as coffee or tea, as a safe and convenient stimulant due to its caffeine content. Research has shown Guarana to be a great stimulant, thermogenic, appetite-suppressing and diuretic, which makes guarana an ideal supplement for overall workout and fitness purposes. Guarana is also high in antioxidants, a good memory enhancer, used as nervine(balances/calms nerves), and is cardiotonic (tones, balances, strengthens the heart).
Guarana seeds contain up to 4-8% caffeine (25,000 to 75,000 ppm), as well as trace amounts of theophylline (500 to 750 ppm) and theobromine (300 to 500 ppm). They also contain large quantities of alkaloids, terpenes, tannins, flavonoids, starch, saponins, and resinous substances.
The xanthine alkaloids (caffeine, theophylline, theobromine) are believed to contribute significantly to guarana's therapeutic activity. In clinical studies, theophylline stimulates the heart and central nervous system, enhances alertness and alleviates fatigue. It also has strong diuretic activity and reduces constriction of the bronchials, making it useful in asthma.
Research has found guarana to be as an effective energy tonic, increase mental acuity, and to enhance long-term memory. An in vivo research study has shown guarana to increase physical activity of rats, increase physical endurance under stress, and increase memory with single doses as well as with chronic doses. The study also revealed that a whole-seed extract performed more effectively than did a comparable dosage of caffeine or ginseng extract. The plant also was found to enhance memory retention and to have an anti-amnesic activity in mice and rats.
Not to be used during pregnancy or while breast-feeding.
Guarana is a caffeine-based stimulant, and as such, people have varying levels of tolerance. About 15% of adults are sensitive to caffeine. Excessive consumption of caffeine is contraindicated for persons with high blood pressure, cardiac disorders, diabetes, ulcers, epilepsy, and other disorders.