August 30, 2016


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How does Yerba Mate work?

Mate contains caffeine and other chemicals which stimulate the brain, heart, muscles lining blood vessels, and other parts of the body.

Are there safety concerns?

Yerba mate is POSSIBLY SAFE for most people, when taken by mouth for short periods of time. It contains caffeine, which can cause some side effects such as inability to sleep (insomnia), nervousness and restlessness, stomach upset, nausea and vomiting, increased heart rate and breathing, high blood pressure, headache, ringing in the ears, irregular heartbeats, and other side effects.

When taken in large amounts or for long periods of time, yerba mate is POSSIBLY UNSAFE. It increases the risk of mouth, esophageal, laryngeal, kidney, bladder, and lung cancer. This risk is especially high for people who smoke or drink alcohol.

When taken in very large amounts, yerba mate is LIKELY UNSAFE, due to its caffeine content.

Special Precautions & Warnings:

Children: Yerba mate is POSSIBLY UNSAFE for children when taken by mouth. Yerba mate is linked with an increased risk of mouth cancer, esophageal cancer, laryngeal cancer, kidney cancer, bladder cancer, and lung cancer.

Pregnancy and breast-feeding: Yerba mate is POSSIBLY UNSAFE when taken by mouth during pregnancy. One concern is that using yerba mate seems to increase the risk of getting cancer. It's not known whether that risk is transferred to the developing fetus. Another concern is the caffeine content of yerba mate. Caffeine crosses the placenta and enters the fetus' bloodstream, producing caffeine levels in the fetus that resemble the caffeine level in the mother. In general, mothers should avoid consuming more than 200 mg of caffeine daily; that's about 2 cups of coffee or tea. Infants born to mothers who consume a lot of caffeine during pregnancy sometimes show symptoms of caffeine withdrawal after birth. High doses of caffeine have also been linked with miscarriage, premature delivery, and low birth weight. However, researchers studied mothers who drank yerba mate tea during pregnancy and found no strong link between drinking yerba mate and premature delivery or small birth weight. But this study has been criticized because it did not consider the amount of yerba mate or caffeine used by the mothers; it looked only at how often they used yerba mate.

Yerba mate is also POSSIBLY UNSAFE during breast-feeding. It is not known whether the cancer-causing chemicals in yerba mate pass into breast milk, but that is a concern. The caffeine in yerba mate is also a problem. It might cause irritability and increased bowel movements in nursing infants.

Alcoholism: Heavy alcohol use combined with long-term yerba mate use increases the risk of cancer from 3-fold to 7-fold.

Anxiety disorders: The caffeine in yerba mate might make anxiety disorders worse.

Bleeding disorders: Caffeine might slow clotting. As a result, there is a concern that the caffeine in yerba mate might make bleeding disorders worse. But so far, this effect has not been reported in people.

Heart conditions: Caffeine in yerba mate can cause irregular heartbeats in certain people. If you have a heart condition, discuss using yerba mate with your healthcare provider.

Diabetes: Some research suggests that the caffeine in yerba mate may affect the way people with diabetes process sugar and may complicate blood sugar control. There is also some interesting research that suggests caffeine may make the warning symptoms of low blood sugar in people with type 1 diabetes more noticeable. Some studies show that the symptoms of low blood sugar are more intense when they start in the absence of caffeine, but as low blood sugar continues, symptoms are greater with caffeine. This might increase the ability of people with diabetes to detect and treat low blood sugar. However, the downside is that caffeine might actually increase the number of low-sugar episodes. If you have diabetes, talk with your healthcare provider before using yerba mate.

Diarrhea. Yerba mate contains caffeine. The caffeine in yerba mate, especially when taken in large amounts, can worsen diarrhea.

Irritable bowel syndrome (IBS): Yerba mate contains caffeine. The caffeine in yerba mate, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.

Glaucoma: Using yerba mate increases the pressure inside the eye due to the caffeine it contains. The increase in pressure occurs within 30 minutes and lasts for at least 90 minutes. If you have glaucoma, discuss your use of yerba mate with your healthcare provider.

High blood pressure: The caffeine in yerba mate might increase blood pressure in people with high blood pressure. Consuming 250 mg of caffeine can increase blood pressure in healthy people, but this doesn't seem to happen in people who use caffeine all the time.

Weak bones (osteoporosis): Some researchers have found that postmenopausal women who drink a liter or more daily of a traditional South American yerba mate tea have higher bone density. However, the caffeine in yerba mate tends to flush calcium out of the body in the urine. This can contribute to weak bones. For this reason, many experts recommend that caffeine intake be limited to less than 300 mg per day (approximately 2-3 cups of yerba mate). Taking extra calcium may help to make up for the calcium that is flushed out.

There are some women who are at special risk for weak bones. These women have an inherited condition that makes it hard for them to use vitamin D properly. Vitamin D works with calcium to build strong bones. These women should be especially careful to limit the amount of caffeine they get from yerba mate as well as other sources.

Smoking: The risk of getting cancer is 3 to 7 times higher in people who smoke and use yerba mate for long periods of time.

Therapeutic Research Faculty copyright

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