If you've perused the label on your favorite energy drink or scanned the aisles of your local supplement store, you've likely seen guarana and taurine make an appearance. Both substances are added to energy drinks and are widely available as dietary supplements. Talk to your health care provider before taking dietary supplements.
Guarana Stimulates Central Nervous System
Guarana is a plant native to the Amazon. It contains caffeine and stimulates the central nervous system, increasing alertness. Guarana supplementation has been shown to improve cognitive performance and decrease mental fatigue, according to Memorial-Sloan Kettering Cancer Center. Side effects include nervousness, irritability, stomach upset, difficulty sleeping and headache.
Taurine May Improve Exercise Performance
Taurine is an amino acid your body makes and is found in meat, poultry and dairy foods. Less is known about the effects of taurine. Scientists think it helps regulate heartbeat and influence brain chemicals called neurotransmitters. Taurine appears to improve exercise performance, according to a study published in the March 2004 edition of the journal "Amino Acids." No adverse effects have been reported when taking taurine at up to 3 grams per day, according to New York University Langone Medical Center.