AmaTea Organic Guayusa Extract
Also known as: Guayusa, Amazonian holly, AmaTea Organic Guayusa Extract, Ilex guayusa
Overview
Guayusa, scientifically known as *Ilex guayusa*, is a leaf from a plant native to the Amazon region, traditionally consumed as a tea. It is a herbal supplement primarily used for cognitive enhancement, mood improvement, and as a natural stimulant. Its active compounds include caffeine, theobromine, chlorogenic acids, flavonoids, and catechins, which contribute to its stimulating and antioxidant properties. Research on guayusa is emerging, with studies indicating acute cognitive and mood benefits in healthy adults. While generally well-tolerated, it can cause transient increases in blood pressure and heart rate, similar to other caffeinated products. The evidence base is moderate, with some randomized controlled trials (RCTs) supporting its acute effects, but long-term human safety and efficacy data are still limited.
Benefits
Guayusa extract has demonstrated several evidence-based benefits, primarily in acute settings. A randomized, placebo-controlled crossover study showed that guayusa extract significantly improved cognitive performance metrics, including the number of correct responses, reaction time, and total score, within 1 to 2 hours post-ingestion in healthy adults. This suggests its potential as a cognitive enhancer. The same study also reported enhanced mental clarity, focus, concentration, productivity, and happiness compared to placebo, indicating positive effects on mood and subjective cognitive states. Another RCT found that a 600 mg dose optimized mood and cognitive outcomes while minimizing jitteriness, highlighting dose-dependent effects. While guayusa can transiently elevate systolic and diastolic blood pressure for about 2 hours post-ingestion, subchronic toxicology studies in rats have shown no genotoxicity or harmful effects at high doses, suggesting a favorable safety profile comparable to caffeine alone. The strength of evidence for acute cognitive and mood benefits is moderate, based on well-controlled but relatively small human trials.
How it works
Guayusa's primary mechanism of action stems from its active compounds, notably caffeine and theobromine. These compounds act as central nervous system stimulants by antagonizing adenosine receptors in the brain, which leads to increased alertness, reduced fatigue, and enhanced cognitive function. Additionally, guayusa contains chlorogenic acids and catechins, which are potent antioxidants. These compounds may contribute to neuroprotective effects and modulate mood and cognitive performance through various pathways, including reducing oxidative stress and inflammation. The extract is absorbed orally, with caffeine bioavailability similar to other caffeinated beverages, leading to acute effects typically observed within 1 to 2 hours post-ingestion.
Side effects
Guayusa is generally well tolerated in acute human trials and animal studies. The most common side effects are mild and transient increases in blood pressure (5–6 mmHg systolic, 3–4 mmHg diastolic) and heart rate, which typically last for about 2 hours post-ingestion. Jitteriness is a possible side effect, particularly at higher doses (e.g., 1200 mg or more), though it is minimized at optimal doses around 600 mg. Uncommon or rare side effects are not well-documented in humans, but animal toxicology studies (up to 90 days at high doses) have shown no significant genotoxicity or organ toxicity beyond effects comparable to caffeine alone. Due to its caffeine content, guayusa has potential interactions with other stimulants, which could amplify stimulant effects, and with antihypertensive medications, potentially counteracting their effects. Individuals with pre-existing hypertension or cardiovascular conditions should exercise caution or avoid guayusa due to its transient blood pressure increases. There is limited data on special populations; therefore, pregnant or breastfeeding women should avoid guayusa due to its caffeine content and the lack of specific safety studies in these groups.
Dosage
For optimal cognitive and mood benefits with minimal side effects, a dose of approximately 600 mg of guayusa leaf extract is recommended. Higher doses, such as 1200 mg, may increase the risk of side effects like jitteriness without providing proportionally greater benefits. The effects of guayusa typically peak within 1 to 2 hours post-ingestion, aligning with the pharmacokinetics of caffeine, making this an ideal timing for consumption when acute effects are desired. While animal studies suggest safety at very high doses (e.g., >5000 mg/kg), human data on maximum safe doses are limited, so caution is advised against exceeding recommended amounts. Guayusa can be consumed as a standardized leaf extract or as a brewed tea, with similar bioavailability across forms. Absorption occurs in the gastrointestinal tract, and food intake may modulate the rate of absorption.
FAQs
Is guayusa safe for daily use?
Acute studies show good tolerance; however, long-term human safety data are limited. Moderate and occasional use is prudent until more long-term research is available.
How fast do effects appear?
Cognitive and mood effects typically appear within 1 hour of ingestion and can last for up to 2 hours, consistent with caffeine's action.
Does it cause jitteriness?
Lower doses (around 600 mg) are associated with minimal jitteriness. Higher doses, however, increase the risk of experiencing jitteriness.
Can it replace coffee?
Yes, guayusa contains caffeine and other stimulants, making it a viable alternative to coffee, offering similar stimulating effects along with unique polyphenols.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10745489/ – This randomized, placebo-controlled crossover study investigated the acute effects of guayusa extract on cognition and mood in 25 healthy adults. It found significant improvements in cognitive performance and subjective mental clarity, focus, and happiness, along with transient increases in blood pressure, indicating guayusa's potential as a cognitive enhancer.
- https://journals.sagepub.com/doi/10.1177/1091581815625594 – This toxicology study in rats evaluated the general and genetic safety of guayusa concentrate over 90 days. It concluded that guayusa showed no genotoxicity or harmful effects at high doses, with observed effects comparable to those of caffeine alone, supporting its safety profile in animal models.
- https://pmc.ncbi.nlm.nih.gov/articles/PMC11257001/ – This double-blind, placebo-controlled crossover RCT with 25 young adults explored the dose-response effects of guayusa leaf extract on mood and cognition. It determined that a 600 mg dose optimized mood and cognitive outcomes with fewer side effects, while a 1200 mg dose increased jitteriness, providing crucial dosing guidance.
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