Green tea is a powerful antioxidant with several known benefits, which makes it the ideal drink for people with type 2 diabetes. According to certain recent studies, it may boost the absorption of insulin, the hormone produced by the pancreas, and may have positive effects on the part of the pancreas that metabolizes carbohydrates.

According to Statistics Canada, in 2016, 7% of Canadians aged 12 and over (approximately 2.1 million people) declared that they had been diagnosed with diabetes. Diabetes is characterized by an abnormally high level of glucose in the blood. The result of this anomaly is insufficient or incorrect use of insulin. Studies have shown that green tea can be beneficial for people with this chronic illness that is more and more common.

Green tea may help to prevent diabetes. A study in Japan established that, after a 12-week green tea treatment plan, participants who drank the most green tea had reduced their risk of type 2 diabetes by 33%. A significant increase in insulin production was noted1.

Green tea has hypoglycaemic properties which are ideal for preventing type 2 diabetes. It is rich in catechins, molecules that are very high in antioxidants. Catechins allow glucose to enter the body’s cells, which may promote a lower blood sugar level (only among diabetics)2.

Another recent study suggests that epigallocatechin-3-gallate (EGCG), a component of green tea, may play a key role in reducing spikes in blood sugar. Scientific studies have shown that absorption of the EGCG molecule, when it is consumed at the same time as starchy food (cereals, bread, pasta, potatoes, etc.), reduced the spike in blood sugar that occurs after a meal3.

After scrutinizing 17 studies, researchers in China arrived at the conclusion that drinking 1 cup of green tea without sugar or milk 3 times a day had a significant effect on blood sugar4. Several scientists agree that simply drinking a cup of green tea before a meal is beneficial5.

Green tea should not replace hypoglycaemic drugs unless otherwise indicated by a medical doctor.

Références citées

1. Iso, H., Date, C., Wakai, K., Fukui, M., Tamakoshi, A. et le JACC Study Group, 2006. The relationship between green tea and total caffeine intake and risk for self-reported type 2 diabetes among Japanese adults. Annals of Internal Medicine, 144(8): 554-562.

2. Zheng, X.-X., Xu, Y.-L., Li, S.H., Hui, R., Wu, Y.J. et X.H. Huang, 2013. Effects of green tea catechins with or without caffeine on glycemic control in adults: a meta-analysis of randomized controlled trials, American Journal of Clinical Nutrition, 97(4): 750-762.

3. Fu, Z., Zhen, W., Yuskavage, J., et D. Liu, 2011. Epigallocatechin gallate delays the onset of type 1 diabetes in spontaneous non-obese diabetic mice, British Journal of Nutrition, 105(8): 1218-1225.

4. Zheng, X.-X., Xu, Y.-L., Li, S.H., Hui, R., Wu, Y.J. et X.H. Huang, 2013. Effects of green tea catechins with or without caffeine on glycemic control in adults: a meta-analysis of randomized controlled trials, American Journal of Clinical Nutrition, 97(4): 750-762.

5. Park, J.-H., Bae, J.H., Im, S.S. et D.K. Dong, 2014. Green tea and type 2 diabetes, Integrative Medicine Research, 3(1): 4–10.

Autres références

Faria, AM., Papadimitriou, A., Silva, KC., Lopes de Faria, JM., et J.B. Lopes de Faria, 2012. Uncoupling Endothelial Nitric Oxide Synthase Is Ameliorated by Green Tea in Experimental Diabetes by Re-establishing Tetrahydrobiopterin Levels, Diabetes, 61 (7): 1838-1847.

Forester, SC., Gu, Y. et J.D. Lambert, 2012. Inhibition of starch digestion by the green tea polyphenol, (-)-epigallocatechin-3-gallate, Molecular Nutrition and Food Research, 56(11):1647-1654.

Goldman R., The Health Benefits and Risks of Green Tea for People With Type 2 Diabetes, Everyday Health, [En ligne] https://www.everydayhealth.com/type-2-diabetes/diet/green-tea-good-type-2-diabetes/, consulté le 5 novembre 2018.

Mousav, A., Vafa, M., et F. Hoseini, 2013. The effects of green tea consumption on metabolic and anthropometric indices in patients with Type 2 diabetes, Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciencesvol, 18,12: 1080-1086.

Nagao, T., Meguro, S., Hase, T., Otsuka, K, Komikado, M., Tokimitsu, I., Yamamoto, T. et K. Yamamoto, 2009. A catechin-rich beverage improves obesity and blood glucose control in patients with type 2 diabetes, Obesity Journal (Silver Spring). 17(2):310-317.

Ortsäter H., Grankvist, N., Wolfram, S. Kuehn, N. et A. Sjöholm, 2012. Diet supplementation with green tea extract epigallocatechin gallate prevents progression to glucose intolerance in db/db mice, Nutrition & Metabolism, 9:11.