Yerba mate is a species of the holly family (Aquifoliaceae), with the botanical name Ilex paraguariensis. Yerba mate is a flowering tree, widely known as the source of the beverage called mate (beverage), traditionally consumed in central and southern regions of South America, particularly Argentina, Bolivia, southern and center-western Brazil, Uruguay, Paraguay and southern Chile. Yerba mate was initially utilized and cultivated by the Guaraní people and in some Tupí communities in southern Brazil, prior to European colonization. It was scientifically classified by the Swiss botanist Moses Bertoni, who settled in Paraguay in 1895.
Yerba mate can be found in various energy drinks on the market today and is also marketed for its supposed ability to suppress appetite and burn fat (its fat burning effect is attributed to its Caffeine content).
. It is able to reduce LDL cholesterol within 20 days of supplementation and, like many supplements derived from plants, it protects the heart and cardiovascular system.
Yerba mate contains xanthines (like Caffeine), flavonoids (like Quercetin), saponins (likeUrsolic Acid), and cinnamic acid compounds (like Chlorogenic Acid).
Yerba Mates leaves contain a variety of molecules including:
1. Flavonoids such as Quercetin, Kaempferol and Rutin, the latter at 6.10 ± 0.21mg/g dry weight, although it varies on extraction
2. Various (5+) cinnamic acids such as Caffeic, 3,4-dicaffeoylquinic acid, feruloylquinic acid, and Chlorogenic Acid, in which amounts of the latter can degrade by half through freeze drying (10.4 to 5.6mg/g dry weight)
3. Caffeine (at around 17.5mg/g fresh weight Yerba Mate) and related xanthines
4. 27+ different saponins, of which are combinations of Ursolic Acid, acetyl-ursolic acid, oleanolic acid as well as pomolic acid. These three in varying glycosides make up the majority of the saponin content and make up about 3-10mg/g dry weight of the leaves
5. , sometimes referred to as Matenosides
6. Vitamin C
7. Vitamin B1
8. Vitamin B2
The fruit of the Yerba Mate tree (not commonly used in teas) includes:
9. , usually ursolic acid and oleanolic acid
Yerba Mate is frequently referred to as possessing 'Matesaponins'; these are usually glycosides of ursolic acid (ursolic acid bound to sugars). Matenosides also exist, and Matenoside A and B appear to refer to another class of Megastigmane compounds.
The two classes of compounds above are referred to as the 'active' ingredients, although all classes found in Yerba appear to be significantly bioactive.
The fresh leaves of Yerba Mate have the highest polyphenolic and saponin content when compared to leaf extract of dried leaves, but still less overall phenols than Camellia Sinensis (Green Tea). During Yerba Mate processing (consisting of blanching, drying, milling, and aging) saponin and xanthine content both appear to be significantly reduced (xanthines to 89% of original values, saponins to 27% of original value).
Yerba mate has been claimed to have various effects on human health.
1. Weight loss
The first study to evaluate the anti-obesity role of yerba maté was conducted in 2001. In this clinical study, the authors demonstrated that an herbal preparation containing yerba maté (“YGD”, yerba maté; guarana, Paullinia cupana Kunth; and damiana, Turnera diffusa Willd) , reducing the time to perceived gastric fullness, and induced significant weight loss over 45 days in overweight patients. Subsequently, YGD has been demonstrated to produce a robust acute effect on caloric intake and meal duration, suggesting that YGD strengthens within-meal satiation, an effect that may be mediated by the previously reported changes in gastric emptying. Moreover, it was demonstrated the hypocholesterolemic effects of yerba maté in healthy subjects with normo- or dyslipidemia. The authors observed, after 20 and 40 days of treatment, a significantly reduction on the levels of low-density lipoprotein-cholesterol (LDL-C), non-high density lipoprotein cholesterol (non-HDL-C), apolipoprotein B (apo B), the LDL-C/HDL-C ratio and increasing HDL-C.
In addition to human studies, in DdY mice fed with high-fat diet animal models, through various mechanisms, including induction and/or enhancement of intestinal glucagon-like peptide-1 (GLP-1), modulation of serum leptin levels and a possible direct central satiety-stimulatory effect. Data obtained from experiments conducted in diet-induced obesity models have shown that yerba maté suppresses body weight gain and visceral fat accumulation and decreases serum levels of cholesterol, triglycerides, LDL cholesterol, glucose, insulin, pancreatic lipase and leptin.
The molecular mechanisms by which yerba maté regulates obesity have also been studied. In this regard, several studies have been conducted in cellular models and in obese animals to evaluate the effects of yerba maté on several genes related to adipogenesis. This process involves a highly regulated and coordinated cascade of transcription factors, including members of the PPAR, C/EBP and sterol regulatory element-binding protein (SREBP) families, which together lead to the establishment of the differentiated state. In this context, it has been observed that yerba maté modulates adipogenesis by regulating the gene expression levels of pro-adipogenic transcription factors, such as Ppar-γ2 and C/ebp-α, in vivo and in vitro. C/EBP and Ppar-γ2 expression depends on other genes that are also essential to adipogenesis, such as cAMP responsive element binding protein 1 (Creb1) and delta-like 1 homolog ( Drosophila ) (Dlk1); Yerba maté modulates the in vivo and in vitro expression of these genes, thus contributing directly to adipogenesis regulation.
In addition, it has been shown that yerba maté regulates adipogenesis in a β-catenin-dependent manner. The β-catenin-dependent signaling pathway is initiated by the binding of the wingless-type MMTV integration site family (WNT) 1, WNT3a and WNT10b to secreted frizzled-related protein (SFRP) 1 and SFRP5 and low density lipoprotein receptor-related protein (LRP) 5 and LRP6 receptors. The expression of WNT10b stabilizes β-catenin in the cytoplasm, thereby inhibiting adipogenesis. Data indicate that among the WNT proteins, WNT10b is the primary adipogenesis regulator, and WNT1 and WNT3a act synergistically. The binding of WNT to its receptors (SFRP and LRP) inhibits glycogen synthase kinase (GSK)-3, resulting in the hypophosphorylation of β-catenin. β-Catenin translocates to the nucleus, where it binds to a TCF/LEF transcription factor, repressing the expression of C/EBPα and PPARγ and, therefore, inhibiting adipogenesis. It was demonstrated that yerba maté modulates adipogenesis in vitro and in vivo via the WNT pathway by increasing the mRNA levels of Wnt10B, Wnt3A, Sfrp1 and Lrp5, which favor the nuclear translocation of β-catenin, thereby increasing the expression of Tcf7l2. An increase in Tcf7l2 (transcription factor 7-like 2 (T-cell specific, HMG-box)) could lead to the repression of C/ebpα and Ppar-γ2, thereby reducing adipogenesis. In addition, it has been shown that the GATA and Krüppel-like zinc finger (KLF) proteins also directly affect adipogenesis. It has been suggested that increased expression of GATA-2 and GATA-3 suppresses adipocyte differentiation through a direct repression of C/EBP-α and PPARγ. Regarding KLF, it has been demonstrated that KLF2 inhibits adipogenesis by inhibiting PPARγ. It was observed that yerba maté enhanced the gene expression of Gata2, Gata3 and Klf2, which may contribute to the inhibition of adipogenesis via the PPARγ pathway. Taking into account that yerba maté is rich in several bioactive compounds, it has been attempted to assess whether any of these compounds would have a greater effect in the inhibition of adipogenesis. The results from these showed that synergism between these compounds might be responsible for the results observed in the yerba maté intervention group.
(The positive effects of yerba maté (Ilex paraguariensis) in obesity, 2015)
2. Cardiovascular Health
Yerba Mate, at 1-2g/kg bodyweight, has been shown to inhibit pancreatic lipase in mice. In vitro analysis showed a dose-dependent increase in inhibition until Yerba Mate hit 3mg/mL, corresponding to 9mg of Yerba Mate extract per gram of enzyme substrate (in this case, fatty acids) and with a 79+/-1.3% inhibition. Weight gain was attenuated with Mate, but fecal fat analysis was not conducted to assess fat malabsorption.  This lipase inhibition appears to be related to the matesaponins, and a pure water extract of yerba mate seems to be less effective in vitro (58%) than other extracts (88-95%) as the most potent lipase inhibitor are fat soluble.
[ 1 ] Maté tea inhibits in vitro pancreatic lipase activity and has hypolipidemic effect on high-fat diet-induced obese mice, 2010
[ 2 ] Brazilian natural medicines. III. structures of triterpene oligoglycosides and lipase inhibitors from mate, leaves of ilex paraguariensis, 2009
An ex vivo study using blood from volunteers found that ingestion of Yerba Mate tea was able to reduce the rate of forced oxidation of LDL induced by copper, but was apparently ineffective at protecting LDL from oxidation induced by lipoxygenase or peroxynitrate. This protection has also been seen in vivo with the HDL molecule in vitro and after consumption of 5g instantized Yerba Mate in adult men.
This protection from lipid peroxidation extends to polyunsaturated fatty acids, as a study in mice livers found reduced rates of PUFA oxidation with Yerba Mate at dosages starting at 0.5g/kg bodyweight and up to 2g/kg bodyweight.
[ 3 ] Effects of maté tea intake on ex vivo LDL peroxidation induced by three different pathways, 2009
[ 4 ] Protective action of Ilex paraguariensis extract against free radical inactivation of paraoxonase-1 in high-density lipoprotein, 2007
[ 5 ] Effects of mate tea (Ilex paraguariensis) ingestion on mRNA expression of antioxidant enzymes, lipid peroxidation, and total antioxidant status in healthy young women, 2009
[ 6 ] Consumption of mate tea (Ilex paraguariensis) decreases the oxidation of unsaturated fatty acids in mouse liver, 2009
An intervention study using 1 liter of Yerba Mate tea daily over a period of 90 days found that LDL cholesterol was significantly decreased (160mg/dL to 150mg/dL) in dyslipidemic women without any dietary changes needed. This same study design was carried out in diabetic and pre-diabetic men to much the same effects, decreasing LDL-C and also improving parameters of glucose metabolism. In both cases, the tea itself did not influence diet significantly yet the other groups fed yerba and given new diets fared better than the groups given yerba in isolation. .
The effects seen with Yerba Mate also appear to be additive to statin therapy, and may offer hope as a adjunct therapy.
Studies that measure lipids over time (usually 20, 40, and 60 days after the start of the study) note a statistically significant improvement in parameters by 20 days, but no further significant improvements over time. Yerba's benefits on lipid parameters appear to manifest fast but may not culminate over time. . .
[ 7 ] Association of mate tea (Ilex paraguariensis) intake and dietary intervention and effects on oxidative stress biomarkers of dyslipidemic subjects, 2012
[ 8 ] Mate tea (Ilex paraguariensis) improves glycemic and lipid profiles of type 2 diabetes and pre-diabetes individuals: a pilot study, 2011
[ 9 ] Consumption of yerba mate ( Ilex paraguariensis ) improves serum lipid parameters in healthy dyslipidemic subjects and provides an additional LDL-cholesterol reduction in individuals on statin therapy, 2009
3. Immunology and Inflammation
Cinnamic compounds in Yerba Mate, the dicaffeoylquinic acids, suppress inflammation and NO release from macrophages (immune cells) by preventing NF-kB from translocating into the nucleus; particularly subunits p50 and p65. The effect seen here (preventing iNOS activation in macrophages) is also seen with both the saponin fraction and the flavonoid fraction, synergistically. The bioactive saponins appear to be oleanolic acid and perhaps pomolic acid, as ursolic acid shows little anti-inflammatory effects.
Yerba Mate extract may also protect macrophages from cytotoxicity (death) induced by nitrosylation, with a potency greater than Green Tea and Red Wine. Nitrosylation is a process by which superoxide radicals bind with Nitric Oxide (NO) to form peroxynitrate (OONO-) and damages cells that tend to form Nitric Oxide such as Macrophages or the endothelium.
[ 10 ] Dicaffeoylquinic acids in Yerba mate (Ilex paraguariensis St. Hilaire) inhibit NF-κB nucleus translocation in macrophages and induce apoptosis by activating caspases-8 and -3 in human colon cancer cells, 2011
[ 11 ] Saponins in yerba mate tea ( Ilex paraguariensis A. St.-Hil) and quercetin synergistically inhibit iNOS and COX-2 in lipopolysaccharide-induced macrophages through NFkappaB pathways, 2009
[ 12 ] Ilex paraguariensis extracts are potent inhibitors of nitrosative stress: a comparative study with green tea and wines using a protein nitration model and mammalian cell cytotoxicity, 2005
Animal studies show that yerba mate modulates signaling pathways that regulate adipogenesis, antioxidant, anti-inflammatory and insulin signaling responses. In summary, the data showed that the use of yerba mate might be useful against obesity, improving the lipid parameters in humans and animal models. In addition, yerba mate modulates the expression of genes that are changed in the obese state and restores them to more normal levels of expression. In doing so, it addresses several of the abnormal and disease-causing factors associated with obesity. Therefore it seems that yerba mate beverages and supplements might be helpful in the battle against obesity and in protecting the cardiovascular system.