The Guayusa Guide

What are the benefits of guayusa?

The established effect of guayusa is the effect of its caffeine: it helps people feel alert. Guayusa leaves also contain theobromine and phenolic compounds such as chlorogenic acids, which show antioxidant activity in laboratory tests. The studies of guayusa in people are few and small, so other health benefits are not proven.

Does guayusa help you feel alert?

Yes, through its caffeine. In a trial published in 2024, 25 adults took a guayusa leaf extract or a placebo. The extract improved mood, perceived energy and psychomotor speed compared with the placebo. It also raised blood pressure by 4 to 5 mmHg, and the higher dose made women feel more jittery. The trial used an extract, not a brewed drink, so its doses do not tell you what one cup or one can does.

Is guayusa rich in antioxidants?

Guayusa leaves contain phenolic compounds. An analysis published in 2017 identified 14 of them, with chlorogenic acid as the main one of its group, and measured a high antioxidant capacity in laboratory tests. A second study of 2017 compared guayusa teas with teas from the tea plant: the guayusa teas had about half of the capacity to scavenge radicals, and a comparable effect in tests on cells.

These are tests in a laboratory. They show what is in the leaf. They do not prove a health effect in people who drink guayusa.

Is the energy of guayusa smoother than the energy of coffee?

People often describe guayusa energy as smooth or sustained. That experience is subjective. One small trial, published in 2016, gave 12 men 200 mg of caffeine from a guayusa leaf extract, from a green coffee extract or as synthetic caffeine. The body absorbed the caffeine of each source in the same way. The guayusa extract caused a smaller rise in epinephrine than the synthetic caffeine. A trial of this size does not prove that guayusa feels different. Compare guayusa with coffee.

What do the people who grow guayusa value in it?

Kichwa families in the Napo province of Ecuador value guayusa for its energizing effect and because it relieves sleepiness, reports a study of their practices published in 2026. This is traditional knowledge. It is not a clinical test.

What is not proven?

Published studies have also tested guayusa for other effects, for example on blood sugar. Those studies used cells or animals, not people. An effect in a laboratory or in an animal does not show that the same effect occurs in a person. Waísa does not claim that guayusa or a Waísa drink prevents or treats a medical condition.

Does guayusa contain L-theanine?

Peer-reviewed guayusa profiles do not currently establish L-theanine as a characteristic compound. Published analyses identify caffeine, smaller amounts of theobromine and phenolic compounds.

Is guayusa safe?

A review published in 2020 found that the known composition of guayusa appears to present no greater risk to health than green tea or yerba mate. The side effects of guayusa are those of caffeine. Read about the side effects of guayusa and who must be careful.

Common questions

What is guayusa good for?

Guayusa contains caffeine, so it helps people feel alert. In a trial published in 2024, a guayusa leaf extract improved mood, perceived energy and psychomotor speed compared with a placebo. Other health benefits are not proven in people.

Does guayusa have antioxidants?

Guayusa leaves contain phenolic compounds such as chlorogenic acids, which show antioxidant activity in laboratory tests. These tests do not prove a health effect in people who drink guayusa.

Does guayusa help you lose weight?

That is not established. The published studies of guayusa in people are small, and they measure alertness, mood and the absorption of caffeine, not body weight.

This page gives general information. It is not medical advice.

Sources

  1. Helwig N. J. and others, Acute, dose-response effects of guayusa leaf extract on mood, cognitive and motor-cognitive performance, and blood pressure, heart rate, and ventricular repolarization, Journal of the International Society of Sports Nutrition, 2024.
  2. Krieger D. R. and others, The Safety, Pharmacokinetics, and Nervous System Effects of Two Natural Sources of Caffeine in Healthy Adult Males, Clinical and Translational Science, 2016.
  3. García-Ruiz A. and others, Guayusa (Ilex guayusa L.) new tea: phenolic and carotenoid composition and antioxidant capacity, Journal of the Science of Food and Agriculture, 2017.
  4. Pardau M. D. and others, Antioxidant and anti-inflammatory properties of Ilex guayusa tea preparations: a comparison to Camellia sinensis teas, Food & Function, 2017.
  5. Espinosa Andrade A. and Vásquez-Castillo W., Socio-cultural components related to the cropping, harvesting, and consumption of guayusa (Ilex guayusa Loes) in Amazonian Kichwa communities, PLoS One, 2026.
  6. Mello T. C. and others, Ilex guayusa Tea Improves Glycaemia and Autonomic Modulation in Female Streptozotocin-Induced Diabetic Rats, Pharmaceuticals, 2025: an example of a study in animals.
  7. Wise G. and Negrin A., A critical review of the composition and history of safe use of guayusa: a stimulant and antioxidant novel food, Critical Reviews in Food Science and Nutrition, 2020.