What are the health benefits of Yerba Mate?
Are there any side effects?
Yerba mate is derived from the leaves of the Ilex paraguariensis tree. This is a broadleaf evergreen tree that can reach up to 50 feet in height. This tree is native to Brazil, Uruguay, Argentina, and parts of Paraguay. The leaves are known as “herb” or “yerba” in Spanish.
The leaves are commercially harvested and contain caffeine, theobromine, and other useful compounds.
An infusion, or mate, is prepared by steeping the dry leaves and twigs of the tree. This is where the name Yerba mate originates.
This product is consumed by over 1 million people worldwide.1
Yerba mate has become a popular ingredient in teas and energy drinks here in the United States.
Health Benefits of Yerba Mate
There are many possible health benefits of yerba mate. I have recently started to enjoy this myself. It is just one of the many new herbal products I have added to my diet.
Here is what I have learned about this tea.
There are several compounds contained in yerba mate that can act as free radical scavengers. A study published in Mutagenesis in July of 2008, concluded that mate tea might protect against DNA damage and improve DNA repair.2
It is well known that oxidative stress contributes to many disease processes.
The antioxidant compounds present in YM may lower the risk of heart disease. Yerba mate has demonstrated the ability to decrease the size of atherosclerotic lesions in animal models.5
Atherosclerosis or “hardening of the arteries” results in restrictive blood flow caused by a buildup of fats, cholesterol, and other substances. These buildups, or “plaques,” can also dislodge, forming a blood clot that may lead to a stroke or pulmonary embolus.
Yerba Mate as a Weight Loss Supplement
Obesity leads to increased morbidity and mortality. The accumulation of visceral fat predisposes people to diseases such as atherosclerosis and type 2 diabetes.6
Mice fed a high-fat diet are excellent models to study obesity.7
Yerba mate has been shown to have positive effects on weight loss. Mice models have demonstrated that mate affects food intake, increases energy expenditures, and leads to a higher basal metabolism.8
This study showed mice fed a high-fat diet (HFD) that received Yerba mate had decreased food and water intake.
Although the body weight in the HFD group increased, the weight gain in the Yerba mate treated group was significantly less than that of the HFD group who didn’t receive the mate.
It should also be noted that Yerba mate appears to have fewer adverse side effects than other natural weight loss supplements.9
Studies using different human groups have found positive effects of satiety and metabolism.10
An article published in 2018 found that the aqueous extracts of the stems and leaves of Ilex paraguariensis possess significant antibacterial activity. I found it fascinating because bacterial strains resistant to the antibiotics we typically use were not immune to the Yerba mate.11
This finding could lead to more effective antibiotics in the future. Bacterial resistance is a significant problem in healthcare today, so newer antibiotics with less resistance could save many lives.
Yerba Mate as a Performance Enhancer
A study performed on well-trained cyclists found Yerba mate increased fat oxidation at low-exercise intensities and improved performance in short time trials.12
Another study found YM ingestion reduced carbohydrate reliance during exercise and augmented fatty acid oxidation.
This was true over a wide range of exercise intensities.13
The investigators concluded that the acute ingestion of YM before exercise increased fat metabolism during light and moderate exercise. No adverse effects on maximal performance were noted.
Adverse Effects of Yerba Mate
All medicinal products have precautions, warnings, and side effects associated with them. I generally use the natural medicines database by trc to research the adverse effects of the various nutraceuticals I study.
Yerba mate may increase the risk of various cancers when used in high doses or over a long period.
The other adverse effects are primarily the result of caffeine. Some of these effects include:
- Chest pain
- Cardiac arrhythmia
- Gastric irritation
- Depressed mood
I have recently started to enjoy Yerba mate. I only drink this occasionally but wanted to research its benefits. I was surprised to find it had promising antibacterial properties. It may also decrease plaque buildup in blood vessels reducing heart attack risk.
Athletes may benefit from its effect on fatty acid oxidation, improving athletic performance, and we all may benefit from its weight loss effects.
Diabetic patients may benefit from its effect on blood glucose levels but must be careful as many YM products contain added sugar.
According to the natural medicines database, this “tea” received a rating of “possibly safe” when used orally and appropriately over a short period.
As with anything, moderation is key. Consuming large doses of YM or long term exposure may increase cancer risk. To be honest, I believe it would be difficult to consume these quantities.
Most of the other adverse effects come from the caffeine content. If you have difficulty with coffee, this may not be the drink for you.
I have not experienced any side effects from Yerba mate. I enjoy the taste and find it very refreshing.
If you have any questions regarding this blog post, or anything related to medications or natural products, please send me an email. I am happy to get an answer for you,
Until next week, be happy, be healthy, and stay safe!
Michael J. Brown, RPh, BCPS, BCPP
Mr. Brown is a Clinical Pharmacist specializing in pharmacotherapy and psychiatry.
Feel free to send Michael a message using this link.
Disclosure: This post may contain affiliate links, meaning, at no additional cost to you, I may earn a commission if you click on, or make a purchase through a third-party link.
- Alkhatib, A. Yerba Maté (Illex Paraguariensis) ingestion augments fat oxidation and energy expenditure during exercise at various submaximal intensities. Nutr Metab (Lond) 11, 42 (2014).
- Miranda DD, Arçari DP, Pedrazzoli J Jr, et al. Protective effects of mate tea (Ilex paraguariensis) on H2O2-induced DNA damage and DNA repair in mice. Mutagenesis. 2008;23(4):261-265. doi:10.1093/mutage/gen011
- Rocha DS, Casagrande L, Model JFA, Dos Santos JT, Hoefel AL, Kucharski LC. Effect of yerba mate (Ilex paraguariensis) extract on the metabolism of diabetic rats. Biomed Pharmacother. 2018;105:370-376. doi:10.1016/j.biopha.2018.05.132
- Lutomski P, Goździewska M, Florek-Łuszczki M. Health properties of Yerba Mate. Ann Agric Environ Med. 2020;27(2):310-313. doi:10.26444/aaem/119994
- Mosimann AL, Wilhelm-Filho D, da Silva EL. Aqueous extract of Ilex paraguariensis attenuates the progression of atherosclerosis in cholesterol-fed rabbits. Biofactors. 2006;26(1):59-70. doi:10.1002/biof.5520260106
- Review Adipose tissue, inflammation, and cardiovascular disease. Berg AH, Scherer PE Circ Res. 2005 May 13; 96(9):939-49.
- Review Inflammation, obesity and comorbidities: the role of diet. Bulló M, Casas-Agustench P, Amigó-Correig P, Aranceta J, Salas-Salvadó J Public Health Nutr. 2007 Oct; 10(10A):1164-72.
- Kang YR, Lee HY, Kim JH, et al. Anti-obesity and anti-diabetic effects of Yerba Mate (Ilex paraguariensis) in C57BL/6J mice fed a high-fat diet. Lab Anim Res. 2012;28(1):23-29. doi:10.5625/lar.2012.28.1.23
- Pittler MH, Schmidt K, Ernst E. Adverse events of herbal food supplements for body weight reduction: systematic review. Obes Rev. 2005;6(2):93-111. doi:10.1111/j.1467-789X.2005.00169.x
- Alkhatib A, Tsang C, Tiss A, et al. Functional Foods and Lifestyle Approaches for Diabetes Prevention and Management. Nutrients. 2017;9(12):1310. Published 2017 Dec 1. doi:10.3390/nu9121310
- Noureddine T, El Husseini Z, Nehme A, Abdel-Massih RM. Antibacterial activity of Ilex paraguariensis (Yerba Mate) against Gram-positive and Gram-negative bacteria. J Infect Dev Ctries. 2018;12(2.1):13S. Published 2018 Feb 22. doi:10.3855/jidc.10037
- Areta JL, Austarheim I, Wangensteen H, Capelli C. Metabolic and Performance Effects of Yerba Mate on Well-trained Cyclists. Med Sci Sports Exerc. 2018;50(4):817-826. doi:10.1249/MSS.0000000000001482
- Alkhatib, A. Yerba Maté (Illex Paraguariensis) ingestion augments fat oxidation and energy expenditure during exercise at various submaximal intensities. Nutr Metab (Lond) 11, 42 (2014). https://doi.org/10.1186/1743-7075-11-42