由巴西聖卡塔琳娜聯邦大學（Federal University of Santa Catarina）的 G. A. Klein 教授領導的研究小組進行的瑪黛茶對糖尿病的效果研究，其研究結果2011年發表在美國著名的營養學雜誌《 The Journal of American College of Nutrition 》第5期上，論文名為《 Mate tea (Ilex paraguariensis) improves glycemic and lipid profiles of type 2 diabetes and pre-diabetes individuals: a pilot study 》，內文指出：每天喝三杯（330ml）的瑪黛茶，二個月後糖尿病人的血糖、血脂有所下降，血糖略有升高的糖尿病前期的患者血脂有明顯的下降。
實驗選取了 29 位 2 型糖尿病病人和 29 位糖尿病前期的病人，分成三組，分 別給予瑪黛茶治療、飲食控制干預、以及瑪黛茶加飲食干預治療。分別在基線、20天、40天、60天做飲食攝入調查和採血化驗。
結果顯示：2型糖尿病組，空腹血糖下降25mg/dl，糖化血紅蛋白下降0.85%，低密度脂蛋白膽固醇LDL下降13.5mg/dl。而患者飲食攝入的總熱量、蛋白質、碳水化合物、脂肪、纖維素含量均保持不變。
糖尿病前期組給予瑪黛茶加飲食干預後，LDL下降了11mg/dl，非高密度脂蛋白膽固醇下降21.5mg/dl，甘油三酯下降了53mg/dl。同時飲食攝入調查發現：總脂肪攝入減少了14%，膽固醇攝入減少了28%，而纖維素攝入增加了35%。
以下是這篇瑪黛茶功效研究論文的原文摘要：
Abstract
Objectives: Yerba mate (Ilex paraguariensis) infusions have been shown to reduce plasma glucose in animals and serum lipids in humans. The aim of this study was to evaluate the effects of roasted mate tea consumption, with or without dietary counseling, on the glycemic and lipid profiles of individuals with type 2 diabetes mellitus (T2DM) or pre-diabetes.
Methods: Twenty-nine T2DM and 29 pre-diabetes subjects were divided into 3 groups: mate tea, dietary intervention, and mate tea and dietary intervention. Individuals drank 330 mL of roasted mate tea 3 times a day and/or received nutritional counseling over 60 days. Blood samples were collected and food intake was assessed at baseline and after 20, 40, and 60 days of treatments.
Results: Mate tea consumption decreased significantly the levels of fasting glucose (25.0 mg/dL), glycated hemoglobin A1c (HbA1c) (0.85%), and low-density lipoprotein cholesterol (LDL-c) (13.5 mg/dL) of T2DM subjects (p < 0.05); however, it did not change the intake of total energy, protein, carbohydrate, cholesterol, and fiber. In pre-diabetes individuals, mate tea consumption combined with nutritional counseling diminished significantly the levels of LDL-c (11 mg/dL), non–high-density lipoprotein cholesterol (HDL-c) (21.5 mg/dL), and triglycerides (53.0 mg/dL) (p < 0.05). Individuals of this group decreased significantly their consumption of total fat (14%), cholesterol (28%), and saturated (23.8%) and monounsaturated (28.0%) fatty acids, and increased their fiber intake by 35% (p < 0.05).
Conclusions: Mate tea consumption improved the glycemic control and lipid profile of T2DM subjects, and mate tea consumption combined with nutritional intervention was highly effective in decreasing serum lipid parameters of pre-diabetes individuals, which may reduce their risk of developing coronary disease.
此外，你也可瀏覽巴西媒體的新聞報導：
Yerba Mate Assists Diabetics in Controlling Blood Sugar
September 13, 2012
TRINDADE, Brazil
Diabetes affects an estimated 24 million Americans. There is no cure but drinking Yerba mate may minimize risk and possibly stop progression of the disease, according to a study in Journal of American College of Nutrition.
Yerba mate (Ilex paraguariensis) infusions have been demonstrated to reduce plasma glucose in animals and serum lipids in humans. The current study was intended to evaluate the effect of roasted mate tea consumption on the glycemic and lipid profiles of men and women with type 2 diabetes mellitus (T2DM) or pre-diabetes.
Involved in the study were 29 people with diabetes mellitus type 2 and 29 with pre-diabetes who were divided into 3 groups, subject to different interventions: mate tea regimen, dietary intervention, and mate tea and dietary intervention. The mate tea regimen required subjects to drink 330 mL of roasted mate tea 3 times a day for over 60 days and the dietary intervention meant nutritional counseling also over 60 days. Food intake was assessed and blood samples were analysed at baseline, and 20, 40, and 60 days of treatments.
In diabetes mellitus type 2 patients, mate tea drinking decreased the levels of fasting glucose by 25.0 mg/dL, glycated hemoglobin A(1c) (HbA(1c)) by 0.85%, and low-density lipoprotein cholesterol (LDL-c) by 13.5 mg/dL, all reductions were significant; Drinking mate tea did not change intakes of total energy, protein, carbohydrate, cholesterol, and fiber in this group of patients.
In those with prediabetes, drinking mate tea coupled with nutritional counseling lowered the levels of LDL-c by 11 mg/dL, non-high-density lipoprotein cholesterol (HDL-c) by 21.5 mg/dL, and triglycerides by 53.0 mg/dL, all reductions were significant. Subjects in this group decreased intakes of total fat (14%), cholesterol (28%), and saturated (23.8%) and monounsaturated (28.0%) fatty acids, and increased fiber intake by 35%.
The study was conducted by G.A. Klein at Federal University of Santa Catarina, Campus Universitario s/n, Trindade, Brazil and colleagues.
The researchers concluded “Mate tea consumption improved the glycemic control and lipid profile of T2DM (diabetes mellitus type 2) subjects, and mate tea consumption combined with nutritional intervention was highly effective in decreasing serum lipid parameters of pre-diabetes individuals, which may reduce their risk of developing coronary disease.”
Diabetes mellitus type 2 or type 2 diabetes mellitus is easy to prevent by following a healthy diet and or taking some supplements. Taking 6 grams of curcumin per day for a couple of months can be effective in preventing prediabetes from progressing into type 2 diabetes mellitus, according to one study conducted by Indian researchers.
Diabetes can be controlled by taking medications and following a healthy lifestyle. If left untreated, the disease can lead to serious complications.