Human Research

Metabo_Thin_ResearchHuman trials of guarana while are rare, they typically study a combination of Guarana with another ingredient, such as tea. However, they do show promise to promote weight loss.

Guarana-green tea extract mixture may boost metabolism

Fourteen healthy men took a mixture of green tea and guarana extracts that was standardized to 200mg caffeine and either 90, 200, 300, or 400mg EGCG, a catechin compound found in green tea. All doses resulted in an energy expenditure (measure of calories burned by the body) increase of roughly 750 kilojoules for the next 24 hours.

  • The researchers concluded that “the EGCG–caffeine mixture should be considered as a good complement in a weight-loss programme

Habitual guarana intake is associated with reduced risk of obesity and metabolic syndrome

637 elderly participants (60 and older) were classified as either habitual guarana drinkers since childhood, or those who never took it. The researchers found that the habitual group had lower prevalence of hypertension (43% vs 53%), obesity (32% vs 47%), and metabolic syndromes such as diabetes (21% vs 32%). The researchers suggest that the xanthines and other compounds in Guarana are likely responsible for this effect, but the exact mechanism is unknown.

  • The researchers concluded that “the results described in this study suggest that habitual guaraná ingestion contributes positively to the prevention of various metabolic disorders in the elderly

Catechins 690 mg may lead to a reduction of body fat

This study looked at the effect of ingesting tea containing 690mg catechins daily for 12 weeks. The 35 male subjects were split up into either the 22mg or 690mg-supplemented groups. The 690mg group was found to have lost 3.7% more fat and 1.5% more overall body weight than the 22mg group.

The researchers attributed this to catechins increasing energy expenditure and directly reducing body fat by a mild amount. Although this study did not look at Guarana directly, it still useful since Guarana has a notable catechin content which may play a role in its effects.

  • The researchers concluded that “long-term consumption of beverages containing catechins inhibits the formation of oxidized lipids such as MDA-LDL, and this is a risk factor for developing arteriosclerosis. Moreover, catechin intake decreases body fat

Tannins and catechins may be effective for inhibiting fat digestion

This study reviewed a wide array of natural compounds that could help obesity by inhibiting the digestion of fat. Among these the authors mention the effects of polyphenols such as tannins and catechins, which are believed to inhibit several enzymes required for the digestion of dietary fat, including pancreatic lipase, lipoprotein lipase, and others. Since Guarana contains both tannins and catechins, it is possible that they play a part in its supposed weight loss benefits.

  • The authors concluded that “…new natural products are being identified and screened for their PL inhibitory potential. Some of these extracts are obtained from plants that are rich in polyphenols and saponins and show inhibitory effects on fat digestion…”

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  • Heckman MA. et al. Caffeine (1, 3, 7-trimethylxanthine) in foods: a comprehensive review on consumption, functionality, safety, and regulatory matters. J Food Sci. 2010 Apr;75(3):R77-87
  • Andersen T. and Fogh J. Weight loss and delayed gastric emptying following a South American herbal preparation in overweight patients. J Hum Nutr Diet. 2001 Jun;14(3):243-50.
  • Hursel R. et al. The effects of catechin rich teas and caffeine on energy expenditure and fat oxidation: a meta-analysis. Obes Rev. 2011 Jul;12(7):e573-81
  • Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Med. 2001;31(11):785-807.
  • Belza A, Toubro S, Astrup A. The effect of caffeine, green tea and tyrosine on thermogenesis and energy intake. Eur J Clin Nutr. 2009 Jan;63(1):57-64
  • Martínez-Pinilla E. Oñatibia-Astibia A, Franco R. The relevance of theobromine for the beneficial effects of cocoa consumption. Front Pharmacol. 2015; 6: 30.
  • Peters EJ, Klein S, Wolfe RR. Effect of short-term fasting on the lipolytic response to theophylline. Am J Physiol. 1991 Oct;261(4 Pt 1):E500-4.
  • Awika JM, Rooney LW. Sorghum phytochemicals and their potential impact on human health. Phytochemistry. 2004 May;65(9):1199-221.
  • Nagao T. et al. Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men. Am J Clin Nutr. 2005 Jan;81(1):122-9.
  • Awika JM, Rooney LW. Sorghum phytochemicals and their potential impact on human health. Phytochemistry. 2004 May;65(9):1199-221.
  • Lima WP. et al. Lipid metabolism in trained rats: effect of guarana (Paullinia cupana Mart.) supplementation. Clin Nutr. 2005 Dec;24(6):1019-28.
  • Bérubé-Parent S. et al. Effects of encapsulated green tea and Guarana extracts containing a mixture of epigallocatechin-3-gallate and caffeine on 24 h energy expenditure and fat oxidation in men. Br J Nutr. 2005 Sep;94(3):432-6.
  • Krewer Cda C. et al. Habitual intake of guaraná and metabolic morbidities: an epidemiological study of an elderly Amazonian population. Phytother Res. 2011 Sep;25(9):1367-74.
  • Nagao T. et al. Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men. Am J Clin Nutr. 2005 Jan;81(1):122-9.
  • De la Garza AL. et al. Natural Inhibitors of Pancreatic Lipase as New Players in Obesity Treatment. Planta Med. 2011 May;77(8):773-85