Green Tea For Weight Loss

Index of Contents →

Share this article

Listen to this article on Spotify, watch it on YouTube, 或者用中文读。

Green tea, celebrated for its potential weight loss benefits, boasts a potent antioxidant called epigallocatechin gallate (EGCG). In this article, we’ll unravel the science behind EGCG and guide you on incorporating green tea into your weight loss journey.

The Origins of Green Tea

Green tea originates from the leaves of the Camellia sinensis plant, native to China and East Asia. Although now globally consumed, the most esteemed varieties still hail from China, Japan, and other parts of Asia with centuries-old cultivation traditions.

Typically grown in mild, humid climates like China, Japan, and Southeast Asia, tea plants thrive with ample rainfall, well-drained soil, and moderate sunlight. Harvested in spring, the first flush of new leaves is considered the most tender and flavorful.

Harvesting involves delicately plucking the top two leaves and a bud from each branch, requiring skill to ensure the leaves are picked at the right growth stage for high-quality tea.

Comparisons

EGCG vs. Green Tea Extract

While EGCG and green tea extract are related, they aren’t interchangeable. EGCG, a type of catechin found in green tea, represents a flavonoid. Green tea extract is a concentrated form of active ingredients in green tea, including EGCG and other catechins.

Green tea extract, often used in dietary supplements, may include various catechins and additional compounds, while EGCG supplements are specifically formulated for high EGCG concentrations.

In green tea, EGCG content varies based on factors like tea type, growing conditions, and brewing method. A cup typically contains 30-50 mg of EGCG, with matcha green tea potentially reaching 70 mg, while sencha green tea may have around 30 mg.

Supplement EGCG levels can be much higher, depending on purity and dosage.

Green vs. Black vs. Oolong Tea

Derived from the same Camellia sinensis plant, green, black, and oolong teas undergo distinct processing, resulting in unique flavors, aromas, and health benefits.

Green tea involves quick steaming or pan-firing to preserve its natural green color and delicate flavor. Rolled and dried leaves create a light, refreshing tea rich in antioxidants like catechins.
Black tea, fully oxidized before drying and rolling, has a dark color, strong flavor, and higher caffeine content. The oxidation process yields compounds like theaflavins and thearubigins, known for antioxidant and anti-inflammatory properties.
Oolong tea, a partially oxidized variety, falls between green and black teas in flavor and caffeine content. It offers a lighter, fragrant profile compared to black tea but is stronger and more flavorful than green tea. Like green tea, oolong tea is rich in catechins and contains additional beneficial compounds found in black tea.

Side Effects

Green tea and its supplements are generally well-tolerated. If there are side effects, they’re often mild, such as gas, bloating, or stomach disturbances. Occasionally, individuals may experience insomnia due to the caffeine in green tea.

While there are occasional reports linking green tea supplements, specifically EGCG, to liver damage, the evidence is not entirely clear or consistent. Cases of liver damage are mostly associated with high supplement doses, often combined with other supplements or medications. Individuals with pre-existing liver conditions may face a higher risk.

Interaction with Medications

Using EGCG supplements alongside certain medications requires attention to potential interactions:

Blood Thinners: EGCG may increase bleeding risks when taken with blood thinning medications like warfarin, aspirin, or clopidogrel.
Stimulants: Green tea extracts, especially those with caffeine, can enhance the effects of stimulants like caffeine or pseudoephedrine, possibly causing rapid heartbeat, high blood pressure, or anxiety.
Chemotherapy Drugs: EGCG might interfere with the effectiveness of some chemotherapy drugs, making it crucial to consult with a healthcare provider before using EGCG supplements during chemotherapy.
Blood Pressure Medications: Interaction risks exist with certain blood pressure medications, including calcium channel blockers, beta-blockers, and ACE inhibitors. EGCG may amplify their effects, potentially causing low blood pressure or other adverse reactions.

Green Tea’s Benefits For Weight Loss

Green tea is might aid in weight loss in several ways:

Metabolism Boost: Green tea contains caffeine and EGCG, a compound that can increase metabolism and fat burning, helping to burn more calories.
Appetite Reduction: Studies suggest that the catechins in green tea may reduce appetite, leading to lower calorie intake and potential weight loss.
Fat Breakdown: Green tea has been shown to enhance the breakdown of body fat, contributing to weight loss.
Fat Absorption Inhibition: The EGCG in green tea can inhibit the absorption of dietary fat, potentially preventing excess calories from being stored as body fat.
Anti-Inflammatory Properties: Green tea’s antioxidants may help reduce inflammation, which is linked to weight gain and obesity.

While some studies conducted on cells and small animals show positive effects, the translation to human bodies is still debated. Human trials have yielded mixed results, with some studies indicating modest weight loss benefits, especially when combined with caffeine and high catechin levels.

Incorporating green tea into a weight loss plan might be beneficial, but it’s essential to consider individual responses. Some find success by replacing high-calorie drinks with green tea, but similar effects can be achieved with water or other teas.

The caffeine content in green tea appears to play a significant role in its potential weight loss effects, possibly contributing more than the EGCG content.

Practical Tips

If you’re considering green tea for weight loss, it’s advisable to drink the actual steeped tea throughout the day. Green tea supplements with EGCG may have other health benefits, but they are not specifically recommended for weight loss.

If opting for a supplement, here are some tips:

Choose a Quality Supplement: Select a reputable brand with high-quality ingredients independently tested for purity.
EGCG Standardization: Look for supplements with standardized EGCG doses (around 25-50%) for transparency.
Follow Recommended Dosage: Adhere to the recommended dosage to avoid potential harm from excessive EGCG intake.
Take with a Meal: Consuming EGCG with a meal containing fat may enhance absorption.
Combine with Exercise: Green tea extract, containing caffeine, can complement an exercise routine.

Top supplement choices

Caffeine anhydrous – 1 cap / day
Green tea (caps) – 2 to 4 caps / day
Green tea (teabags, decaf) – 1 to 4 cups / day
Green tea (teabags) – 1 to 4 cups / day

Learn more about

Citations

Asbaghi O, Fouladvand F, Gonzalez MJ, Aghamohammadi V, Choghakhori R, Abbasnezhad A. Effect of Green Tea on Anthropometric Indices and Body Composition in Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis. Effekt von grünem Tee auf anthropometrische Indizes und die Körperzusammensetzung bei Patienten mit Diabetes mellitus Typ 2: eine systematische Übersicht und Metaanalyse. Complement Med Res. 2021;28(3):244-251. doi:10.1159/000511665

Auvichayapat, P., Prapochanung, M., Tunkamnerdthai, O., Sripanidkulchai, B. O., Auvichayapat, N., Thinkhamrop, B., Kunhasura, S., Wongpratoom, S., Sinawat, S., and Hongprapas, P. Effectiveness of green tea on weight reduction in obese Thais: A randomized, controlled trial. Physiol Behav 2-27-2008;93(3):486-491.

Basu A, Sanchez K, Leyva MJ, et al. Green tea supplementation affects body weight, lipids, and lipid peroxidation in obese subjects with metabolic syndrome. J Am Coll Nutr. 2010;29(1):31-40. doi:10.1080/07315724.2010.10719814

Brown AL, Lane J, Holyoak C, Nicol B, Mayes AE, Dadd T. Health effects of green tea catechins in overweight and obese men: a randomised controlled cross-over trial. Br J Nutr. 2011;106(12):1880-1889. doi:10.1017/S0007114511002376

Caffeine content for coffee, tea, soda and more https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/caffeine/art-20049372

Chantre P, Lairon D. Recent findings of green tea extract AR25 (Exolise) and its activity for the treatment of obesity. Phytomedicine 2002;9:3-8.

Diepvens K, Westerterp KR, Westerterp-Plantenga MS. Obesity and thermogenesis related to the consumption of caffeine, ephedrine, capsaicin, and green tea. Am J Physiol Regul Integr Comp Physiol. 2007;292(1):R77-R85. doi:10.1152/ajpregu.00832.2005

Dostal AM, Arikawa A, Espejo L, Kurzer MS. Long-Term Supplementation of Green Tea Extract Does Not Modify Adiposity or Bone Mineral Density in a Randomized Trial of Overweight and Obese Postmenopausal Women. J Nutr. 2016;146(2):256-264. doi:10.3945/jn.115.219238

Gahreman D, Heydari M, Boutcher Y, Freund J, Boutcher S. The Effect of Green Tea Ingestion and Interval Sprinting Exercise on the Body Composition of Overweight Males: A Randomized Trial. Nutrients. 2016;8(8):510. Published 2016 Aug 19. doi:10.3390/nu8080510

Green Tea Extract-Containing Natural Health Products – Rare Risk of Serious Liver Injury. Recalls & alerts. November 15, 2017. http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2017/65100a-eng.php. Accessed November 10, 2017

Han S, Abiko Y, Washio J, Luo Y, Zhang L, Takahashi N. Green Tea-Derived Epigallocatechin Gallate Inhibits Acid Production and Promotes the Aggregation of Streptococcus mutans and Non-Mutans Streptococci. Caries Res. 2021;55(3):205-214. doi:10.1159/000515814

Health Product InfoWatch – October 2016, Green Tea Triple Fat Burner. https://www.canada.ca/en/health-canada/services/drugs-health-products/medeffect-canada/health-product-infowatch/health-product-infowatch-october-2016.html#a15

Hill AM, Coates AM, Buckley JD, Ross R, Thielecke F, Howe PR. Can EGCG reduce abdominal fat in obese subjects?. J Am Coll Nutr. 2007;26(4):396S-402S. doi:10.1080/07315724.2007.10719628

Hsu CH, Liao YL, Lin SC, Tsai TH, Huang CJ, Chou P. Does supplementation with green tea extract improve insulin resistance in obese type 2 diabetics? A randomized, double-blind, and placebo-controlled clinical trial. Altern Med Rev. 2011;16(2):157-163.

Hsu CH, Tsai TH, Kao YH, Hwang KC, Tseng TY, Chou P. Effect of green tea extract on obese women: a randomized, double-blind, placebo-controlled clinical trial. Clin Nutr. 2008;27(3):363-370. doi:10.1016/j.clnu.2008.03.007

Hursel R, Viechtbauer W, Westerterp-Plantenga MS. The effects of green tea on weight loss and weight maintenance: a meta-analysis. Int J Obes (Lond). 2009;33(9):956-961. doi:10.1038/ijo.2009.135

Janssens PL, Hursel R, Westerterp-Plantenga MS. Long-term green tea extract supplementation does not affect fat absorption, resting energy expenditure, and body composition in adults. J Nutr. 2015;145(5):864-870. doi:10.3945/jn.114.207829

Jurgens TM, Whelan AM, Killian L, Doucette S, Kirk S, Foy E. Green tea for weight loss and weight maintenance in overweight or obese adults. Cochrane Database Syst Rev. 2012;12(12):CD008650. Published 2012 Dec 12. doi:10.1002/14651858.CD008650.pub2

Kapoor MP, Sugita M, Fukuzawa Y, Okubo T. Physiological effects of epigallocatechin-3-gallate (EGCG) on energy expenditure for prospective fat oxidation in humans: A systematic review and meta-analysis. J Nutr Biochem. 2017;43:1-10. doi:10.1016/j.jnutbio.2016.10.013

Kovacs EM, Lejeune MP, Nijs I, Westerterp-Plantenga MS. Effects of green tea on weight maintenance after body-weight loss. Br J Nutr. 2004;91(3):431-437. doi:10.1079/BJN20041061

Lin Y, Shi D, Su B, et al. The effect of green tea supplementation on obesity: A systematic review and dose-response meta-analysis of randomized controlled trials. Phytother Res. 2020;34(10):2459-2470. doi:10.1002/ptr.6697

Matsuyama T, Tanaka Y, Kamimaki I, Nagao T, Tokimitsu I. Catechin safely improved higher levels of fatness, blood pressure, and cholesterol in children. Obesity (Silver Spring). 2008;16(6):1338-1348. doi:10.1038/oby.2008.60

Momose Y, Maeda-Yamamoto M, Nabetani H. Systematic review of green tea epigallocatechin gallate in reducing low-density lipoprotein cholesterol levels of humans. Int J Food Sci Nutr. 2016;67(6):606-613. doi:10.1080/09637486.2016.1196655

Nagao T, Hase T, Tokimitsu I. A green tea extract high in catechins reduces body fat and cardiovascular risks in humans. Obesity (Silver Spring). 2007;15(6):1473-1483. doi:10.1038/oby.2007.176

Ohishi T, Fukutomi R, Shoji Y, Goto S, Isemura M. The Beneficial Effects of Principal Polyphenols from Green Tea, Coffee, Wine, and Curry on Obesity. Molecules. 2021 Jan 16;26(2):453. doi: 10.3390/molecules26020453. PMID: 33467101; PMCID: PMC7830344.

Phung OJ, Baker WL, Matthews LJ, et al. Effect of green tea catechins with or without caffeine on anthropometric measures: a systemic review and meta-analysis. Am J Clin Nutr 2010;91:73-81.

Scholey A, Downey LA, Ciorciari J, et al. Acute neurocognitive effects of epigallocatechin gallate (EGCG). Appetite. 2012;58(2):767-770. doi:10.1016/j.appet.2011.11.016

Vázquez Cisneros LC, López-Uriarte P, López-Espinoza A, Navarro Meza M, Espinoza-Gallardo AC, Guzmán Aburto MB. Efectos del té verde y su contenido de galato de epigalocatequina (EGCG) sobre el peso corporal y la masa grasa en humanos. Una revisión sistemática [Effects of green tea and its epigallocatechin (EGCG) content on body weight and fat mass in humans: a systematic review]. Nutr Hosp. 2017;34(3):731-737. Published 2017 Jun 5. doi:10.20960/nh.753

Vilela MM, Salvador SL, Teixeira IGL, Del Arco MCG, De Rossi A. Efficacy of green tea and its extract, epigallocatechin-3-gallate, in the reduction of cariogenic microbiota in children: a randomized clinical trial. Arch Oral Biol. 2020;114:104727. doi:10.1016/j.archoralbio.2020.104727

Wang H, Wen Y, Du Y, et al. Effects of catechin enriched green tea on body composition. Obesity (Silver Spring). 2010;18(4):773-779. doi:10.1038/oby.2009.256

Westerterp-Plantenga MS. Green tea catechins, caffeine and body-weight regulation. Physiol Behav. 2010;100(1):42-46. doi:10.1016/j.physbeh.2010.02.005

Wolfram S. Effects of green tea and EGCG on cardiovascular and metabolic health. J Am Coll Nutr. 2007;26(4):373S-388S. doi:10.1080/07315724.2007.10719626

Xie L, Tang Q, Yao D, et al. Effect of Decaffeinated Green Tea Polyphenols on Body Fat and Precocious Puberty in Obese Girls: A Randomized Controlled Trial. Front Endocrinol (Lausanne). 2021;12:736724. Published 2021 Oct 12. doi:10.3389/fendo.2021.736724

Zhang S, Zhu Q, Chen JY, OuYang D, Lu JH. The pharmacological activity of epigallocatechin-3-gallate (EGCG) on Alzheimer’s disease animal model: A systematic review. Phytomedicine. 2020;79:153316. doi:10.1016/j.phymed.2020.153316

Zheng G, Sayama K, Okubo T, Juneja LR, Oguni I. Anti-obesity effects of three major components of green tea, catechins, caffeine and theanine, in mice. In Vivo. 2004;18(1):55-62.