What Is Yerba Mate?
Yerba mate (Ilex paraguayenis) is a tree native to the rainforests of South America. A member of the holly family, the tree produces leaves and stems that have long been used to make tea in Brazil, Paraguay, and Argentina. Consumed as a beverage, yerba mate tea (often simply called "yerba mate") is also used in traditional medicine to treat various health problems.
Uses for Yerba Mate
Yerba mate proponents claim that the tea can help with these health concerns:
Benefits of Yerba Mate
To date, research on yerba mate's health effects is very limited. Existing studies suggest that the tea and/or yerba mate extract may be useful for the following:
1) Weight Loss
In a 2001 study of 47 healthy overweight adults, researchers found that taking a mixed herbal preparation (containing yerba mate, guarana, and damiana) three times daily for 45 days induced significant weight loss. The herbal blend also helped participants feel full more quickly while eating.
A more recent study on mice (published in 2009) found that yerba mate may modulate the expression of several obesity-related genes and, in turn, produce a potent anti-obesity effect.
2) Cardiovascular Problems
Yerba mate extract may help attenuate heart-muscle dysfunction resulting from ischemia (a condition that occurs when blockage in a coronary artery reduces blood flow to the heart), according to a 2005 study on rats.
3) DNA Repair
A study published in 2008 found that yerba mate helped neutralize free radicals and protect mice from DNA damage, a hallmark of cancer and other diseases.
Yerba Mate and Cancer
A number of studies have linked chronic consumption of yerba mate with increased risk of bladder, esophageal, lung, and head and neck cancers. Although researchers have yet to determine how or why yerba mate might raise cancer risk, there's evidence that steeping the tea at high temperatures may promote the absorption of certain carcinogenic compounds found in the plant.
Safety Concerns for Yerba Mate
Due to yerba mate's caffeine content, people with high blood pressure, heart disease, and anxiety should avoid the tea or extract. Women who are pregnant or breastfeeding should also avoid yerba mate.
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