Yerba Mate, also known as erva-mate in portugues, is a herbal tea that originates from South America. It is made from an infusion of the dried leaves of Ilex paraguariensis.

Traditionally, Yerba Mate is often drank out of a dried gourd using a metal straw called "bombilla".  The dry leaves (about 50 g) are packed into the gourd and hot water is poured over them; this is then repeated multiple times, with as much as half to 1 L of water.

Besides as a stiumlant, traditionally, Yerba Mate is used for treatment of arthritis, slow digestions, liver diseases, headache, rheumatism, and obesity, among others.

Nutritional Value of Yerba Mate

Yerba Mate is rich in polyphenols and minerals, with the concentration varying depending on the variety, growing condition and processing. Among the polyphenols in Yerba Mate are caffeine, caffeic acid, catechin, epicatechin gallate, quercetin. These polyphenols have antioxidant activity, the ability to scavenge oxidative stress causing free radicals. Its antioxidant activity is suggested to be significantly higher than green tea (13.1 nmol TEAC/μg equivalents gallic acid in Yerba Mate vs. 9.1 nmol TEAC/μg equivalents gallic acid in green tea).

The caffeine level in Yerba Mate is comparable to coffee, 78 mg of caffeine in a 150 ml of Yerba Mate compared 85 mg of caffeine in 150 ml of coffee.

Minerals in Yerba Mate include aluminum, manganese, potassium, zinc, choline, copper and more.Yerba Mate is also a source of chlorophyll.

Health Benefits of Yerba Mate

Yerba Mate, due its  phytochemicals (some high in antioxidant activity), is known to be associated with reduced risks of many diseases that are caused by free radicals.

High lights of possible benefits of Yerba Mate:

  • reduction in lipid peroxidation, DNA damage, cell death.
  • reduction in risk factors for diabetes.
  • reduction in LDL cholesterol oxidation, a precursor for atherosclerosis.
  • inhibition of toxic effects of some highly reactive chemicals (eg.  peroxynitrite) that are associated with stroke and myocardial ischemia, restriction in blood supply.
  • contains chemicals associated with reduced risks of cancer. It has shown the ability to inhibit growth cancer cells.
  • may help in weight loss and management.

Below is a table with a list of chemicals, Yerba Mate is known to contain, and summary of the potential effects of the chemicals.

PolyphenolHealth benefits
Caffeine Anticarcinogenic, antiobesity, antioxidant, antitumor, diuretic, vasodilator
Chlorogenic-acid Antioxidant, analgesic, antiatherosclerotic, antibacterial, antidiabetic, antitumor, choleretic
Chlorophyll Antibacterial, anticancer
Choline Antidiabetic, cholinergic, lipotropic
Nicotinic acid Choleretic, hypocholesterolemic 1 to 6 g/day
Pantothenic acid Antiallergic 100 to 500 mg/day, antiarthritic 500 to 2000 mg/day, antifatigue
Rutin Antioxidant, antitumor, antitumor-promoter, antiulcer, vasodilator
Tannin Antioxidant, antitumor, antitumor-promoter, lipoxygenase-inhibitor, MAO-inhibitore
Theobromine diuretic, stimulant, myorelaxant
Theophylline diuretic, choleretic, stimulant, vasodilator, myorelaxant
Ursolic acid Analgesic, antioxidant, antiperoxidant  antiarrhythmic, anticancer, antialzheimer
Adapted from Heck and Mejia (2007).

 

Yerba Mate Side Effects

There are studies that have reported a positive association between Yerba Mate consumption and incidence of certain kinds of cancers. These include bladder  and oral cancer.  The association may be due to some cancer causing molecules found in Yerba Mate or just other factors such as smoking which are also common habits among people, study subjects, who drink Yerba Mate.

 
References:
C. I.  Heck and de Mejia, E.G de Mejia. Yerba Mate Tea (Ilex paraguariensis): A Comprehensive Review on Chemistry, Health Implications, and Technological Considerations. J. of Food Sci., 2007, 72(9): R138-R151.

Eduardo De Stefani, Paolo Boffetta, Hugo Deneo-Pellegrini, Pelayo Correa, Alvaro L Ronco, Paul Brennan, Gilles Ferro, Giselle Acosta and María Mendilaharsu. Non-alcoholic beverages and risk of bladder cancer in Uruguay. BMC Cancer 2007,7:57

M. Bates, C. Hopenhayn, O. Rey, L. Moore. Bladder cancer and mate consumption in Argentina: A case-control study. Cancer Letters, 2007,  246 (1-2):268-273.