Health Effects of Guarana

Guarana (Paullinia cupana) is a climbing vine and member of the maple family. Native to the Amazon basin, the majority of guarana cultivated for commercial purposes is grown in Brazil. The seeds of the fruit are reputed to possess several health effects, such as the ability to improve cognition and promote weight loss. In addition to delivering twice the amount of caffeine than coffee beans, the seeds contain the alkaloids theobromine and theophylline.

Cognitive Effects

• Research on the health effects of guarana include a particular interest in the potential cognitive effects of the plant, most notably in terms of enhanced memory and alertness. When initial research indicated that guarana improved memory recall in rats compared to a placebo, British medical scientists set out to test the effects of guarana on the central nervous system in people. Their findings, published in the Jan. 21, 2007, issue of the Journal of Psychopharmacology, showed that low dosages of about 75 mg of guarana markedly improved alertness, memory and mood.

Weight Loss

• In a 2001 study conducted at the Charlottenlund Medical Centre in Denmark, 44 obese but otherwise healthy people participated in a placebo-controlled trial in which they were either given an herbal combination of guarana, yerba mate and damiana or a placebo. The research team, led by Dr. Torben Andersen, found that the subjects supplementing with the herbal formula lost an average of 11 pounds within 45 days. In contrast, the placebo group only lost an average of 1 pound in the same time frame. An interesting side note to these findings is that the study subjects also experienced a longer sensation of feeling full due to delayed gastric emptying of up to 20 minutes.

Cellulite Reduction

• In another study using mice supplemented with either conjugated linoleic acid (CLA) or guarana and CLA, researchers noted a significant reduction in the size of fat cells in both groups within 6 weeks, suggesting a possible treatment for cellulite. However, the group treated with guarana and CLA exhibited a 50 percent greater reduction in fat cell size. Additional details of this study can be read in the May 2002 issue of the Journal of Nutrition.

Other Claims

• Additional health benefits of guarana not yet substantiated by clinical research include the treatment of migraine, rheumatism, neuralgia and arteriosclerosis.

Side Effects

• Since guarana contains a substantial amount of caffeine, some people may experience unwanted side effects, especially at high dosages. Common side effects reported include anxiety, hyperactivity, heart palpitations and insomnia. In addition, this herb should be avoided during pregnancy and breast-feeding.