BMC Complementary and Alternative MedicineThe official journal of the International Society for Complementary Medicine Research (ISCMR)201515:338
DOI: 10.1186/s12906-015-0859-1
© Kim et al. 2015
Received: 12 February 2015
Accepted: 11 September 2015
Published: 25 September 2015
Abstract
Background
Obesity is a major health problem. A food field research that has recently aroused considerable interest is the potential of natural products to counteract obesity. Yerba Mate may be helpful in reducing body weight and fat. The aim of this study was to investigate the efficacy and safety of Yerba Mate supplementation in Korean subjects with obesity.
Methods
A randomized, double-blind, placebo-controlled trial was conducted. Subjects with obesity (body mass index (BMI) ≥ 25 but < 35 kg/m2 and waist-hip ratio (WHR) ≥ 0.90 for men and ≥ 0.85 for women) were given oral supplements of Yerba Mate capsules (n = 15) or placebos (n = 15) for 12 weeks. Subjects take three capsules per each meal, total three times in a day (3 g/day). Measured outcomes were efficacy (abdominal fat distribution, anthropometric parameters and blood lipid profiles) and safety (adverse events, laboratory test results and vital signs).
Results
During 12 weeks of Yerba Mate supplementation, decreases in body fat mass (P = 0.036) and percent body fat (P = 0.030) compared to the placebo group were statistically significant. WHR was significantly decreased (P = 0.004) in the Yerba Mate group compared to the placebo group. No clinically significant changes in any safety parameters were observed.
Conclusions
Yerba Mate supplementation decreased body fat mass, percent body fat and WHR. Yerba Mate was a potent anti-obesity reagent that did not produce significant adverse effects. These results suggested that Yerba Mate supplementation may be effective for treating obese individuals.
Trial registration
ClinicalTrials.gov: (NCT01778257)
Keywords
Yerba Mate Ilex paraguariensis Obesity Clinical trialsBackground
Obesity is a major health problem. Overweight and obesity are defined by the World Health Organization (WHO) as abnormal or excessive fat accumulation that increases the risk of type 2 diabetes, cardiovascular disease and several types of cancers [1, 2]. Obesity continues to be one of the biggest global challenges in the 21st century, with at least 2.8 million adults dying each year from conditions resulting from being overweight and obeses [3].
Many efforts to overcome obesity have focused on developing anti-obesity agents. Among drugs, fenfluramine, dexfenfluramine and sibutramine reduce energy intake, suppress hunger and enhance satiety [4]. However, only a few of these drugs enter and stay in the market because most are associated with serious side effects. Common side effects include insomnia, dry mouth, constipation, nausea and headache. In addition, sibutramine is associated with increased blood pressure and pulse rate, ventricular and supraventricular tachyarrhythmias and angina pectoris, raising concerns about a potential increase in cardiac risk [5, 6]. Because of potential adverse side effects, anti-obesity drugs are recommended to be prescribed for obesity only when the benefits of treatment clearly outweigh the risks. Whereas drug for antiobesity is effective but with some concern about side effect, most functional foods that are generally considered safe have not been scientifically validated for treating obesity or their effects are not statistically significant [7, 8].
Yerba Mate, the dried leaves of the plant Ilex paraguariensis, is currently consumed by over 1 million people worldwide, traditionally in many South American countries including Argentina, Brazil, Uruguay, Paraguay. More recently, Yerba Mate tea has been consumed in North America and Europe [9]. Yerba Mate beverages are reported to have biological activities, probably due to their high polyphenol content. Phenolic compounds have long been known to possess biological functions. In addition to polyphenols such as flavonoids (quercetin and rutin) and phenolic acids (chlorogenic and caffeic acids), Yerba Mate is also rich in caffeine and saponins [10]. Yerba Mate extracts are especially rich in chlorogenic acids that might contribute to hypocholesterolemic [11] and weight loss effects [12]. Chlorogenic acid inhibits adipogenesis by reducing the expression of genes regulating adipogenesis in 3T3-L1 cells and in mouse model of HFD-induced obesity [13]. In these regards, it is likely that Yerba Mate may potential alternative for controlling body fat accumulation and weight. In vitro and in vivo studies have demonstrated that Yerba Mate modulates signaling pathways, has chemopreventive activities [14, 15], enhance intestinal propulsion [16], has vasodilatation effects [17], inhibits glycation [18], inhibits oxidative stress [19] and has inflammatory effects [20]. Yerba Mate suppresses body weight gain and visceral fat accumulation and decreases serum levels of cholesterol, triglycerides, LDL cholesterol [21, 22]. Our previous study reported that Yerba Mate reduces body weight in mice with obesity induced by a high-fat diet. After feeding animals Yerba Mate for 4 weeks, we observed a decrease in total cholesterol, leptin levels and blood glucose that ultimately led to reduce their body weight [23]. Taking into account that Yerba Mate is especially rich in chlorogenic acid and several bioactive compounds, it suggest that it is possible to inhibit obesity.
Based on encouraging results from animal studies, we performed a clinical trial to evaluate the anti-obesity effects of Yerba Mate on humans. The objective of the study was to document the effects of 12 weeks of Yerba Mate supplementation on body fat composition in obese Korean people using a randomized, double-blind, placebo-controlled protocol.
