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Effect of yerba mate and green tea on paraoxonase and leptin levels in patients affected by overweight or obesity and dyslipidemia: a randomized clinical trial.
Balsan, G, Pellanda, LC, Sausen, G, Galarraga, T, Zaffari, D, Pontin, B, Portal, VL
Nutrition journal. 2019;18(1):5
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Yerba mate is a popular tea-like beverage, traditionally consumed in Latin and South America. Yerba mate contains a range of plant compounds that may have beneficial effects on health, such as weight loss and antioxidant activity. This study aimed to evaluate the effect of the intake of yerba mate and green tea on serum levels of leptin, a hormone involved in regulating appetite, and paraoxonase-1 (PON-1), an enzyme that can destroy harmful oxidised fats in the blood. 142 overweight or obese adults aged 35-60 years, with abnormal levels of fats in the blood and no history of coronary artery disease took part in this controlled, randomised clinical trial. Participants drank 1 litre of either yerba mate, green tea or apple tea daily for eight weeks. Blood PON-1 and leptin levels were measured at the beginning and end of the study. The group drinking yerba mate showed a significant 9.7% increase in blood levels of PON-1, but no difference in leptin levels. The consumption of green tea resulted in no significant differences in the levels of PON-1 or leptin. The increase in PON-1 levels in the yerba mate group was significantly associated with increased levels of high-density lipoprotein (HDL-c - often called ‘good’ cholesterol). The authors concluded that drinking yerba mate increased antioxidant capacity by increasing blood levels of PON-1 and was positively associated with increased HDL-c, demonstrating a protective role of this beverage against thickening and hardening of the arteries.
Abstract
BACKGROUND This study aimed to evaluate the effect of the intake of yerba mate (YM) and green tea (GT) on serum levels of leptin and paraoxonase-1 (PON-1), compared to control. METHODS Controlled, randomized clinical trial (RCT) that evaluated 142 men and women affected by overweight or obesity aged 35-60 years, untreated dyslipidemia and no history of coronary artery disease. Participants were randomized to ingest 1000 mL GT, YM or apple tea (AT, control group) daily, during eight weeks. Serum PON-1 and leptin levels were analyzed by ELISA immunoassay at the beginning (baseline) and after eight weeks of intervention. RESULTS The intake of 1 l of YM/day resulted in significant increase in serum levels of PON-1 (9.7%; p = 0.005). The consumption of GT induced no significant difference in the levels of PON-1 (p = 0.154) and leptin (p = 0.783). Intergroup analysis showed a significant difference (p = 0.036) in the variation of PON-1 levels in the YM group when compared to GT and AT groups. In addition, the increase in PON-1 levels in the YM group was significantly associated with increased HDL-c (p = 0.004). CONCLUSIONS The intake of yerba mate increased the antioxidant capacity by increasing serum levels of PON-1 and was positively associated with increased HDL-c, stressing the protective role of this beverage against atherosclerotic diseases. GT intake had no significant effect on serum levels of PON-1 and leptin. TRIAL REGISTRATION This study is registered with ClinicalTrials.gov under protocol number NCT00933647.
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Role of whole grains versus fruits and vegetables in reducing subclinical inflammation and promoting gastrointestinal health in individuals affected by overweight and obesity: a randomized controlled trial.
Kopf, JC, Suhr, MJ, Clarke, J, Eyun, SI, Riethoven, JM, Ramer-Tait, AE, Rose, DJ
Nutrition journal. 2018;17(1):72
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Poor diet is the leading risk factor for premature death and disability in the United States. Poor diets lead to metabolic syndrome and its associated diseases such as heart disease and diabetes. The purpose of this study was to determine the impact of increasing intake of wholegrains or fruit and vegetables against a typical Western diet on inflammatory makers and gut microbiota composition. The study was a randomized, parallel arm feeding trial which enrolled fifty-two participants. The subjects were randomized into three groups (control, wholegrains, and fruit and vegetables). Results indicate that the wholegrain and fruit and vegetable diets had significant positive impacts on inflammatory markers. Interestingly, while both treatment groups decreased inflammatory markers, each decreased a different biomarker. The treatments induced individualised changes in microbiota composition such that treatment group differences were not identified. Authors conclude that wholegrain and fruit and vegetable diets have a positive impact on metabolic health in individuals affected by overweight or obesity.
Abstract
BACKGROUND Whole grains (WG) and fruits and vegetables (FV) have been shown to reduce the risk of metabolic disease, possibly via modulation of the gut microbiota. The purpose of this study was to determine the impact of increasing intake of either WG or FV on inflammatory markers and gut microbiota composition. METHODS A randomized parallel arm feeding trial was completed on forty-nine subjects with overweight or obesity and low intakes of FV and WG. Individuals were randomized into three groups (3 servings/d provided): WG, FV, and a control (refined grains). Stool and blood samples were collected at the beginning of the study and after 6 weeks. Inflammatory markers [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), lipopolysaccharide binding protein (LBP), and high sensitivity C-reactive protein (hs-CRP)] were measured. Stool sample analysis included short/branched chain fatty acids (S/BCFA) and microbiota composition. RESULTS There was a significant decrease in LBP for participants on the WG (- 0.2 μg/mL, p = 0.02) and FV (- 0.2 μg/mL, p = 0.005) diets, with no change in those on the control diet (0.1 μg/mL, p = 0.08). The FV diet induced a significant change in IL-6 (- 1.5 pg/mL, p = 0.006), but no significant change was observed for the other treatments (control, - 0.009 pg/mL, p = 0.99; WG, - 0.29, p = 0.68). The WG diet resulted in a significant decrease in TNF-α (- 3.7 pg/mL; p < 0.001), whereas no significant effects were found for those on the other diets (control, - 0.6 pg/mL, p = 0.6; FV, - 1.4 pg/mL, p = 0.2). The treatments induced individualized changes in microbiota composition such that treatment group differences were not identified, except for a significant increase in α-diversity in the FV group. The proportions of Clostridiales (Firmicutes phylum) at baseline were correlated with the magnitude of change in LBP during the study. CONCLUSIONS These data demonstrate that WG and FV intake can have positive effects on metabolic health; however, different markers of inflammation were reduced on each diet suggesting that the anti-inflammatory effects were facilitated via different mechanisms. The anti-inflammatory effects were not related to changes in gut microbiota composition during the intervention, but were correlated with microbiota composition at baseline. TRIAL REGISTRATION ClinicalTrials.gov , NCT02602496 , Nov 4, 2017.