Study supports Guayusa leaf extract’s cognitive and mood benefits
Data published in the Journal of the International Society of Sports Nutrition indicated that a 600 mg dose of AmaTea Max by Applied Food Sciences significantly improved mood scores as well as measures of fatigue-inertia, perceived energy, motor speed and psychomotor speed.
In addition, a higher dose (1,200 mg) of the guayusa leaf extract (GLE) decreased reaction times during a neurocognitive hop test, thereby supporting benefits for motor-cognitive performance, reported scientists from the University of Iowa.
“This is the first study to examine the dose-dependent effects of acute GLE supplementation on mood, perceived energy, focus, jitteriness, cognitive and motor-cognitive performance, and on heart rate, blood pressure and ventricular repolarization,” the researchers wrote. “Our findings indicate that acute GLE supplementation improves cognitive and motor-cognitive performance, mood, and perceived energy.”
AmaTea
Ilex guayusa is a species of holly tree native to the Amazon rainforest. The botanical contains caffeine, chlorogenic acids, phenolic compounds and terpenoids and has a long history of traditional use as a gentle stimulant and source of potent antioxidants.
Applied Food Sciences developed a patented extraction process to produce its AmaTea Max guayusa extract, which is supported by a letter of no objection from the U.S. Food and Drug Administration regarding its GRAS (Generally Recognized as Safe) status (GRAS Notification 870).
The ingredient is supported by other clinical trials, included a recent study that compared the acute effect of the AmaTea Max guayusa extract on cognitive function and e-gaming performance. That study reported a greater kills/match ratio in the game Fortnite vs. caffeine and placebo, as well as increased vigor and reduced fatigue as compared to placebo. AmaTea Max was also named as a finalist in the 2024 NutraIngredients-USA Awards for cognitive function ingredient of the year.
The new randomized, double-blind, placebo-controlled crossover study examined the effects of a single small (600 mg) and larger (1,200 mg) dose of AmaTea Max on a range of mood and cognitive measures, as well as any potential impact on cardiovascular health.
The study was primarily funded by Applied Food Sciences, Inc., with additional funding from the National Center for Advancing Translational Sciences of the National Institutes of Health.
Study details
The University of Iowa researchers recruited 25 young adults (average age of 28) to participate in their study. The volunteers were randomly assigned to consume one of two doses of AmaTea Max: 600 mg (containing 120 mg of caffeine) or 1,200 mg (containing 240 mg of caffeine) or placebo. Each dose was separated by a seven-day washout period before participants crossed over to one of the other groups.
Results showed that the lower dose of the guayusa leaf extract led to significant improvements in total mood disturbance, fatigue-inertia, perceived energy, motor speed and psychomotor speed, compared to placebo.
The higher dose also improved psychomotor speed while also increasing motor-cognitive performance (reaction time). Jitteriness was only observed in women when taking the higher dose group.
In addition, both doses increased systolic and diastolic blood pressure by 4-5 mmHg, the researchers reported.
“Lower dosages of GLE (e.g. 600 mg) appear to optimize cognitive and mood-related outcomes while limiting side-effects such as jitteriness in women, and higher dosages may be necessary (e.g. 1,200 mg) to promote improvements in motor-cognitive performance,” they stated.
“Our findings have important implications for GLE dosing, which should be dependent on the goal of supplementation and the target population,” they concluded.
Source: Journal of the International Society of Sports Nutrition
Volume 21, 2024 - Issue 1, doi: 10.1080/15502783.2024.2379424
“Acute, dose-response effects of guayusa leaf extract on mood, cognitive and motor-cognitive performance, and blood pressure, heart rate, and ventricular repolarization”
Authors: N.J. Helwig, et al.
