John Nguyen
05-21-2006, 01:11 AM
I have a personal interest in drinking tea for health and enjoyment, and have been doing research on what's out there. I found this tea called Yerba Mate (pronounced ma-tae) and wondered if others might have heard of it. It shows promises for ergogenics, thermogenics, mental focus and overall health. Below is a link to some information (be aware that the website sells supplements, too, but there are plenty other more objective information on the tea plant on the internet).
http://www.rain-tree.com/yerbamate.htm
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Excerpt from the website:
BIOLOGICAL ACTIVITIES AND CLINICAL RESEARCH
Researchers in Switzerland performed a study on human subjects (in 1999) that indicated yerba mate could be beneficial as a weight-loss aid. They noticed a thermogenic effect in healthy individuals indicating a rise in the proportion of fat burned as energy. In another study, yerba mate was given in combination with the plants guaraná and damiana. This combination prolonged gastric emptying (which made the subjects feel "fuller" longer) and reduced body weight. Clinical studies indicate yerba mate leaf inhibits lipoxygenase, an enzyme involved in inflammation and inflammatory diseases. Yerba mate extracts also have been shown to relax smooth muscle, to increase bile flow, and inhibit vasoconstriction. A recent (2002) U.S. patent cites yerba mate for inhibiting monoamine oxidase (MAO) activity by 40-50% in vitro, reporting that it might be useful for a variety of such disorders as "depression, disorders of attention and focus, mood and emotional disorders, Parkinson's disease, extrapyramidal disorders, hypertension, substance abuse, eating disorders, withdrawal syndromes and the cessation of smoking."
Yerba mate has significant antioxidant activity, demonstrated in numerous studies. Its high antioxidant values are linked to rapid absorption of known antioxidant plant chemicals found in mate leaves. An infusion of the leaf has been demonstrated to inhibit lipid peroxidation - particularly LDL (low-density lipoprotein) oxidation. Oxidation of LDL is considered to be the initiating factor in the pathogenesis of atherosclerosis. Another study in vitro has shown yerba mate to inhibit the formation of advanced glycation end products (AGEs), with an effect comparable to that of two pharmaceutical AGE inhibitor drugs. The formation of AGEs play a part in the development of diabetic complications.
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I think I may add this to my tea consumption -- I'm into antioxidant, energy, and relaxation.
Johnny
Scott Kolasinski
05-21-2006, 10:28 PM
I have heard of this herb. It is in several thermogenic products out there on the market. I hate tea so I don't have any personal experience with it. It appears that a lot of its benefits and side-effects are attributed to its caffeine content. This is a summary taken from the Natural Medicines Comprehensive Database. If you want any of the references (which I took the majority of them out), send me a private message and I'll give them to you.
MATE
Also Known As:
Chimarrao, Hervea, Ilex, Jesuit's Tea, Maté Folium, Paraguay Tea, St. Bartholemew's Tea, Yerba Mate.
People Use This For:
Orally, mate is used as a stimulant to relieve mental and physical fatigue. It's also used as a diuretic, for modifying mood or affective disorders, as a mild analgesic for headache and rheumatic pains, and as a laxative in large amounts. It is also used orally for depression, weight loss, urinary tract infections (UTIs), chronic fatigue syndrome (CFS), cardiac insufficiency, arrhythmias, hypotension, nervous heart complaints, kidney and bladder stones, and to promote cleansing and excretion of waste.
In foods, the use of mate includes a tea-like beverage.
Safety:
POSSIBLY SAFE ...when used orally and appropriately on a short-term basis (11866).
POSSIBLY UNSAFE ...when mate is used orally in large amounts or for prolonged periods of time. Mate is associated with an increased risk of mouth cancer, esophageal cancer, laryngeal cancer, kidney cancer, bladder cancer, and lung cancer.
LIKELY UNSAFE ...when used orally in very high doses. Mate contains caffeine. The fatal acute oral dose of caffeine is estimated to be 10-14 grams (150-200 mg per kilogram). Serious toxicity can occur at lower doses depending on variables in caffeine sensitivity such as smoking, age, prior caffeine use, etc.
CHILDREN: POSSIBLY UNSAFE ...when used orally. Mate is associated with an increased risk of mouth cancer, esophageal cancer, laryngeal cancer, kidney cancer, bladder cancer, and lung cancer.
PREGNANCY: POSSIBLY UNSAFE ...when used orally. Mate is associated with an increased risk of mouth cancer, esophageal cancer, laryngeal cancer, kidney cancer, bladder cancer, and lung cancer. Teratogenic studies have not been performed. Mate contains caffeine. Caffeine crosses the placenta, producing fetal blood concentrations similar to maternal levels. It is generally recommended that mothers should avoid consuming more than 300 mg of caffeine daily or more than 3 cups of tea or coffee per day. High maternal doses of caffeine throughout pregnancy have resulted in symptoms of caffeine withdrawal in newborn infants. High doses of caffeine have also been associated with spontaneous abortion, premature delivery, and low birth weight; however, one retrospective study of mothers consuming mate tea during pregnancy found no significant association between mate consumption and preterm or small for gestational age births. But this study did not consider the amount of mate or caffeine consumption, only the frequency of consumption.
LACTATION: POSSIBLY UNSAFE ...when used orally. Mate is associated with an increased risk of mouth cancer, esophageal cancer, laryngeal cancer, kidney cancer, bladder cancer, and lung cancer. Whether carcinogenic constituents of mate are transferred via breast milk is unknown. Mate contains caffeine. Consumption of mate might cause irritability and increased bowel activity in nursing infants.
Effectiveness:
INSUFFICIENT RELIABLE EVIDENCE to RATE
Obesity. Mate taken orally might cause weight loss when used in combination with guarana and damiana. More evidence is needed to rate mate for this use.
Mechanism of Action:
The applicable parts of mate are the leaf and leaf stem. It contains caffeine, theobromine, theophylline, phytol, stigmasterol, and squalene. The concentrations of these constituents vary with growing conditions, harvesting, and preparation methods. Mate also contains various minerals including phosphorus, iron, calcium, thiamine, riboflavin, vitamin C, and vitamin E. Other constituents include tannins and N-nitroso compounds that are potential carcinogens.
The usual concentration of caffeine in mate is 0.5% to 0.8% (compared to 1-2% in coffee). The caffeine in mate stimulates the central nervous system (CNS), heart, muscles, and possibly the pressor centers that control blood pressure. Possible mechanisms include adenosine receptor blockade and phosphodiesterase inhibition. By blocking adenosine receptors, caffeine is thought to increase the release of neurotransmitters such as dopamine. Caffeine also decreases airway resistance and stimulates respiration, via adenosine receptor blockade and phosphodiesterase inhibition. It has also been proposed that caffeine may decrease GABA and serotonin signaling. Caffeine stimulates gastric acid secretion, and increases plasma catecholamine levels. Caffeine can have positive inotropic and chronotropic effects on the heart. Caffeine can also acutely elevate both diastolic and systolic blood pressure, but might not have this effect in habitual users.
Caffeine exerts a diuretic effect, with water losses estimated at 1.17 mL per milligram of caffeine. Tachyphylaxis to the diuretic effect develops rapidly, diminishing fluid losses associated with caffeine intake. Caffeine-containing beverages consumed during moderate endurance exercise do not appear to compromise bodily hydration status. Caffeine does not substantially affect the fluid status of people who drink caffeinated beverages on a regular basis.
Caffeine increases resting energy expenditure (REE) and cellular thermogenesis. It also causes an increase in nonoxidative fatty acid turnover and lipid oxidation; however, the net effect on lipid oxidation is small. The effects of caffeine on energy expenditure and lipid metabolism seem to be mediated by both sympathetic and nonsympathetic mechanisms (13733).
Caffeine, a constituent of mate, has been reported to cause increases and decreases in blood glucose. In people with type 2 diabetes, acute administration of caffeine impairs postprandial glucose metabolism, while acute abstention from caffeine reduces postprandial glucose levels by 21%. Whether these effects also occur with caffeinated beverages and herbs is unknown (12374). Other research in obese people suggests that caffeine ingestion may contribute to insulin resistance (12375,13744). However, one study found that patients with type 1 diabetes taking 200 mg of caffeine twice daily had increased frequency and intensity of warning signs of hypoglycemia. This may be due to a reduction in blood flow to the brain and an increase in glucose utilization by the brain. Some clinical research suggests symptoms of hypoglycemia are more intense at onset in the absence of caffeine, but with increasing duration of hypoglycemia, symptoms are greater with caffeine.
In vitro and epidemiological research suggests that mate may be carcinogenic. Carcinogenesis may result from thermal injury; mate is consumed as a hot beverage in South America. Because smoking in combination with mate greatly increases cancer risk, some researchers think that mate might act as a solvent for carcinogens in tobacco.
Adverse Reactions:
Orally, the prolonged use of mate is associated with an increased risk of mouth cancer, esophageal cancer, laryngeal cancer, kidney cancer, bladder cancer, and lung cancer. The effect seems to be cumulative-dose dependent. The risk of cancer with mate use seems to increase if it is taken as a warm beverage. Tobacco and alcohol use can increase risk 7-fold. There is one report of venous occlusive disease associated with excessive, long-term mate consumption.
The caffeine constituent of mate can cause insomnia, nervousness, restlessness, gastric irritation, nausea and vomiting, as well as tachycardia, quickened respiration, tremors, delirium, convulsions, and diuresis. Caffeine may exacerbate sleep disturbances in patients with acquired immunodeficiency syndrome (AIDS).
Caffeine can cause anaphylaxis in sensitive individuals, although true IgE-mediated caffeine allergy seems to be relatively rare (11315).
Large doses of caffeine can cause massive catecholamine release and subsequent sinus tachycardia, metabolic acidosis, hyperglycemia, and ketosis (13734). Other symptoms include headache, anxiety, agitation, ringing in the ears, hypokalemia, respiratory alkalosis, chest pain, premature heartbeat, and arrhythmia. In fatal caffeine overdose, the cause of death is usually ventricular fibrillation.
High doses of mate providing 250 mg of caffeine can also increase blood pressure. This doesn't seem to occur in people who habitually consume caffeine products. Epidemiological research suggests there is no association of caffeine consumption with incidence of hypertension. Habitual coffee consumption doesn't seem to be related to hypertension, but habitual consumption of sugared or diet cola is associated with development of hypertension. Whether chronic use of mate can cause hypertension is unknown.
The existence or clinical importance of caffeine withdrawal is controversial. Some researchers think that if it exists, it appears to be of little clinical significance. Other researchers suggest symptoms such as headache; tiredness and fatigue; decreased energy, alertness, and attentiveness; drowsiness; decreased contentedness; depressed mood; difficulty concentrating; irritability; and lack of clear-headedness are typical of caffeine withdrawal. Withdrawal symptoms such as delirium, nausea, vomiting, rhinorrhea, nervousness, restlessness, anxiety, muscle tension, muscle pains, and flushed face have been described. However, these symptoms may be from nonpharmacological factors related to knowledge and expectation of effects. Clinically significant symptoms caused by caffeine withdrawal may be uncommon.
Some evidence shows caffeine is associated with fibrocystic breast disease, breast cancer, and endometriosis in women; however, this is controversial since findings are conflicting. Restricting caffeine in women with fibrocystic breast conditions doesn't seem to affect breast nodularity, swelling, or pain.
Epidemiological evidence regarding the relationship between caffeine use and the risk for osteoporosis is contradictory. Caffeine can increase urinary excretion of calcium. Women identified with a genetic variant of the vitamin D receptor appear to be at an increased risk for the detrimental effect of caffeine on bone mass. However, moderate caffeine intake, less than 300 mg per day, does not seem to significantly increase osteoporosis risk in most postmenopausal women with normal calcium intake.
Combining ephedra with mate increases the risk of adverse effects, due to the caffeine contained in mate. One unpublished report associated jitteriness, hypertension, seizures, temporary loss of consciousness, and hospitalization requiring life support with the use of a combination ephedra and guarana (caffeine) product. There is one report of ischemic stroke in an athlete who consumed ephedra 40-60 mg, creatine monohydrate 6 grams, caffeine 400-600 mg, and a variety of other supplements daily for six weeks (1275). Some evidence shows caffeine is associated with fibrocystic breast disease, breast cancer, and endometriosis in women; however, this is controversial since findings are conflicting.
MaryB
05-22-2006, 12:13 AM
Hi all - I'm very familiar w/ Yerba Mate, having looked at investing (when I was a professional VC) in one of the larger private companies that markets it nationwide.
The herb itself has been around for centuries and is widely used in Central & South America, originally by native rainforest peoples. Now, it's widely available & has been sold in the US in Whole Foods and natural foods stores for about the past 5-7 yrs; there are now several reputable brands and some of the larger tea/coffee companies have even come out with yerba mate variants that you can get in large mainstream grocery stores.
Some in the natural foods industry have even touted yerba mate as the 'next chai' -- e.g., an interesting, somewhat exotic niche product that could go mainstream in the US.
The herb has definitely got some strong stimulants and that's been its primary claim to fame; most of the mfrs try to market it as a more 'natural' way to get a buzz versus alternative drinks/products. I don't know if there've been any/many safety or toxicology studies done; I do know 3 things:
1) Some varieties definitely have a lot of stimulants in them and can really get you charged up;
2) many people drink it frequently with few ill effects, both the unrefined version available in the rainforest and also the Westernized versions available at Safeway/Whole Foods;
3) As with many herbal products, there's little standardization across manufacturers. The amount of stimulant, degree of 'natural-ness', and the taste profiles vary significantly from brand to brand.
So, caveat emptor regarding both side effects and taste (which can vary even from batch to batch from the same mfr).
One of the more established brands available (based in Santa Cruz) is a company called Guayaki and their products are in Whole Foods & some Safeways which have natural products sets. (I'm not endorsing them, just saying that they're among the larger and better-known companies with some history making and selling varieties of yerba mate.)
FYI. - Mary B