Green tea extract

Green tea helps burn fat

According to recent research, it must be concluded that tea and especially green tea can play a role in and for weight loss. In a study conducted by scientists from the Universities of Geneva and Fribourg in Switzerland, it has been found that green tea has a remarkable effect in burning fat. This fact is almost too good to be true, as green tea already represents one of the most potent substances in the arsenal of natural health-promoting dietary supplements. Before we take a closer look at this ancient, miraculous natural product and the amazing chemical substances it contains, however, let's briefly review the Swiss study.

The Swiss Weight Loss Study

After careful screening, 10 healthy young men aged 24-26 years were selected for the study who ranged in constitution from lean to mild obesity (8-30% body fat) and had a fat percentage of about 35-40% (the typical Western diet) in their daily food intake. The average percentage of body fat is about 20% in healthy young men and 27% in young healthy women. During the aging process we lose muscle mass, while the fat percentage increases on average to about 30% and 40%, respectively. For the entire period of the study (5 - 6 weeks), a precise diet plan was followed in order to be able to perform a standardized weight measurement.

Thus, energy intake consisted of 13% protein, 40% fat, and 47% carbohydrate. In addition: The first group a powdered green tea extract which was approximately equivalent to 4 cups of tea, the second group received the same amount of caffeine accordingly, which is believed to have fat burning properties, while the third group received a placebo. All three groups received these additional nutritional supplements three times a day (breakfast, lunch and dinner) and finally had to stay in a so-called respiration room for 24 hours to allow an accurate measurement of energy turnover or energy expenditure.

Green tea burns fat

Compared to the placebo group, the green tea extract caused a significant increase in energy expenditure, around 4%. This may seem small at first, but a small effect repeated day after day adds up in the end. In addition, 35-43% of this 4% increase is due to the burning of fat. The authors thus conclude that "... oral administration of green tea extract increases fat burning (fat oxidation), leading to weight loss. ..." 3 Caffeine, on the other hand, did not show any remarkable increase in comparison with the placebo group, mainly because the administered amount of 150 mg/daily was below the limit of extra fat burning possible by this substance (thermogenesis).

Another study

According to the latest news, however, the drink is also suitable for athletes, because Japanese scientists from the Biological Science Laboratoies in Tochigi have shown in animal experiments with mice that green tea significantly increases the condition of the animals. The experiment was conducted as follows: The mice had to swim in a counter-current system for as long as possible.

The average swimming time of the rodents was 26 minutes. Subsequently, the animals were either fed a standard diet or additionally received a green tea extract. After 10 weeks of training, there was a clear difference in performance between the two groups of mice. While the normal-fed animals lasted an average of 33 minutes in the countercurrent system as a result of the regular training, the mice "doped" with green tea extract were able to increase their endurance significantly more. These animals were able to increase their performance to an average of 40 minutes. Further studies by the researchers showed that the tea extract increases fat breakdown in the liver. As a result, more energy is made available for muscle work and the animals are able to perform at full capacity for a longer period of time. However, scientists emphasize that this effect is not achieved by a single dose of the extract, but requires regular use. It is suspected that long-term use could lead to a metabolic change that increases fat burning and reduces carbohydrate burning.

And even for seriously injured muscles, green tea can help. Duchenn's muscular atrophy, for example, is a functional disorder characterized by muscle death caused by the deficiency of a protein called dystrophin. A study has now investigated whether the antioxidant components of green tea can delay the tissue death of a muscle in mice that exhibited muscular dystrophy. For four weeks, starting on the day of birth, 0.01 and 0.05 percent green tea extract was added to the diet of the tiny rodents. This supplement significantly reduced tissue death (necrosis) in the fast-twitch fibers in a dose-dependent manner - but it showed no effect on the slow-twitch fibers in the study. To achieve a positive effect in humans as well, one should drink about seven cups of green tea per day.

Thermogenesis

Thermogenesis refers to the generation of heat, particularly as it occurs during physiological processes. In the human body, heat generation occurs primarily through a series of chemical reactions in which carbon dioxide and water molecules are produced from fat molecules. The reactions release thermal energy - heat - part of which, together with the carbon dioxide and water, is released to the outside world primarily through the lungs, skin and excrement.

The heat released can be quantified using various physical units of measurement. One of these is the calorie and thermogenesis thus the way calories are "burned". It could be that the effect of the green tea extract is partly due to the content of caffeine in synergistic interaction with ... ... but with what actually? It is safe to assume that there is another active ingredient in green tea that is responsible for this effect. Well, it is no longer a secret today, since the substance we are looking for is already well known to another group of scientific researchers, namely cancer researchers.

Green tea fights cancer

Green tea is considered to be a substance capable of protecting against certain types of cancer and thus occupies a place of honor among dietary supplements (NEM). Well-controlled studies have shown that green tea is able to protect against cancers of the pancreas, stomach, breast and lungs. No other food supplement can make this claim.

Although there are a variety of chemical substances in green tea, one among them stands out far and is considered by some scientists to be probably the most promising substance in the fight against cancer ever discovered. It is this epigallocatechin gallate (EGCG) and belongs to the class of catechins. These are members of a larger group, the polyphenols, which themselves belong to an even larger group, the flavonoids. You must have heard a lot about flavonoids. These are the colorful pigment substances we know from so many fruits, vegetables and teas. They are known to us for their powerful antioxidant activity and have many well-documented properties for preventing and fighting cancer, heart disease, vision problems, allergies, viral infections, and many other diseases.

Green tea is an antioxidant prodigy

Among all the catechins of green tea, EGCG is by far the most pharmacologically active and effective substance and, fortunately, it is present in the largest quantity compared to more than half of all the other active substances. In the mentioned Swiss study on weight loss, the dose of green tea extract was 375 mg/daily of polyphenols of which 270 mg (72%) was EGCG.

EGCG is an antioxidant that will certainly play a major role in the future. According to a study by the University of Kansas (USA), its antioxidant effect is 100 times greater than that of vitamin C and 25 times greater than that of vitamin E in terms of protecting DNA from free radical damage. In addition, EGCG is able to stop the reproduction of cancer cells and to trigger a natural process of programmed cell death, the so-called apoptosis. Furthermore, EGCG inhibits the production of an enzyme called urokinase, which is required for the growth of cancer cells.

In studies with animals, blocking urokinase production leads to the shrinkage of tumors, sometimes even to their complete disappearance. This may well be one of the most important properties of EGCG. The cancer-preventive properties of green tea are most impressively demonstrated in those parts of the world where it is consumed regularly on a daily basis in relatively large quantities (typically 5 to 10 cups daily). For example, epidemiological studies in Asian countries show low incidence of prostate cancer attributed to green tea consumption compared to Western countries. Laboratory studies on the biological effectiveness of green tea have demonstrated that EGCG causes the death of prostate cancer cells.

Green tea also fights heart disease

Meanwhile, green tea also plays a role in protecting against heart disease.7 A study conducted with rodents showed that green tea is able to reduce the amount of lipids (fats) such as cholesterol, especially LDL (the "bad", the "low-density" cholesterol) in the blood. In addition, it blocks the oxidation of LDL, which reduces the tendency to arterial deposits (hardening of the arteries) and thus to possible heart attacks in the future. At the same time, it contributes to the increase of HDL, the "good" cholesterol, and lowers the level of blood sugar and triglycerides, which may reverse the effects of insulin resistance, which increases with age.

Why does it have to be green tea?

Green tea (Camellia sinensis) is not a special type of tea, but simply the use of very young, low-standing leaves of the tea plant. These are steamed, rolled and dried immediately after cutting and then prepared for the commercial tea product. The more familiar black tea is obtained from the same green leaves, except that they still undergo a fermentation process before being rolled and dried. Oolong tea is an intermediate product with partial fermentation.

The fermentation process is essentially an oxidation process, during which a number of valuable polyphenols in the tea leaves are converted and degraded by enzymatic action into less effective substances, thus at the same time losing part of the medicinal value of the tea. Oxidation processes are not a problem for green tea because the enzymes responsible for the oxidation processes are inactivated during the steaming process. The antioxidant capacity of green tea is 6 times higher than that of black tea.

Caffeine and ephedrine: The dynamic duo

The tea gets its astringent or astringent properties from the tannins it contains (like those found in red wine) and its stimulant properties from the caffeine content. As we have seen, caffeine is a thermogenic agent. Together with ephedrine, it is particularly effective due to synergistic effects between these two substances. Ephedrine is a natural stimulant and thermogenic agent extracted from the plant ephedra. Caffeine and ephedrine not only have a stimulating effect in terms of thermogenesis, but they also suppress appetite. Particularly beneficial is the fact that they promote fat loss, but leave muscle mass untouched. If we now add to this already potent combination the antioxidant capacity of the polyphenol EGCG, then we have a truly powerful trio.

Demand in sport

Take approximately 250-500mg of green tea extract standardized to 50% EGCG 1 to 2 times per day on an empty stomach.

References

1. Yokogoshi H, Kobayashi M. Life Sci. Hypotensive effect of gamma-glutamylmethylamide in spontaneously hypertensive rats. 1998;62(12):1065-8
2. Kakuda T. Neuroprotective effects of the green tea components theanine and catechins. Biol Pharm Bull. 2002 Dec;25(12):1513-8
3. Sadzuka Y, Yamashita Y, Kishimoto S, Fukushima S, Takeuchi Y, Sonobe T. [Glutamate transporter mediated increase of antitumor activity by theanine, an amino acid in green tea]. Yakugaku Zasshi. 2002 Nov;122(11):995-9
4. Kao YH, Hiipakka RA, Liao S. Modulation of endocrine systems and food intake by green tea epigallocatechin gallate. Endocrinology. 2000 Mar;141(3):980-7
5. Sayama K, Lin S, Zheng G, Oguni I. Effects of green tea on growth, food utilization and lipid metabolism in mice. In Vivo. 2000 Jul-Aug;14(4):481-4.
6. Hasegawa N, Yamda N, Mori M. Powdered green tea has antilipogenic effect on Zucker rats fed a high-fat diet. Phytother Res. 2003 May;17(5):477-80.
7. Inoue M, Tajima K, Mizutani M, Iwata H, Iwase T, Miura S, Hirose K, Hamajima N, Tominaga S. Regular consumption of green tea and the risk of breast cancer recurrence: follow-up study from the Hospital-based Epidemiologic Research Program at Aichi Cancer Center (HERPACC), Japan. Cancer Lett. 2001 Jun 26;167(2):175-82
8. Nakachi K, Eguchi H, Imai K. Can teatime increase one's lifetime? Ageing Res Rev. 2003 Jan;2(1):1-10.
9. Conney AH, Lu YP, Lou YR, Huang MT. Inhibitory effects of tea and caffeine on UV-induced carcinogenesis: relationship to enhanced apoptosis and decreased tissue fat. Eur J Cancer Prev. 2002 Aug;11 Suppl 2:S28-36.
10. Zhu M, Gong Y, Yang Z. [Protective effect of tea on immune function in mice]. Zhonghua Yu Fang Yi Xue Za Zhi. 1998 Sep;32(5):270-4.
11. Sato D, Matsushima M. Preventive effects of urinary bladder tumors induced by N-butyl-N-(4-hydroxybutyl)-nitrosamines in rat by green tea leaves. Int J Urol. 2003 Mar;10(3):160-6
12. Edwin D, Geetha VR, Vishwanathan H, Usha Rani MV. An anticlastogenic in vivo micronucleus assay for tea. J Environ Biol. 2002 Oct;23(4):373-6.
13. Umemura T, Kai S, Hasegawa R, Kanki K, Kitamura Y, Nishikawa A, Hirose M. Prevention of dual promoting effects of pentachlorophenol, an environmental pollutant, on diethylnitrosamine-induced hepato- and cholangiocarcinogenesis in mice by green tea infusion. Carcinogenesis. 2003 Jun;24(6):1105-9. epub 2003 Apr 24.
14. Tokunaga S, White IR, Frost C, Tanaka K, Kono S, Tokudome S, Akamatsu T, Moriyama T, Zakouji H. Green tea consumption and serum lipids and lipoproteins in a population of healthy workers in Japan. Ann Epidemiol. 2002 Apr;12(3):157-65.
15. Sasazuki S, Kodama H, Yoshimasu K, Liu Y, Washio M, Tanaka K, Tokunaga S, Kono S, Arai H, Doi Y, Kawano T, Nakagaki O, Takada K, Koyanagi S, Hiyamuta K, Nii T, Shirai K, Ideishi M, Arakawa K, Mohri M, Takeshita A. Relation between green tea consumption and the severity of coronary atherosclerosis among Japanese men and women. Ann Epidemiol. 2000 Aug;10(6):401-8.
16. Yokozawa T, Nakagawa T, Kitani K. Antioxidant activity of green tea polyphenol in cholesterol-fed rats. J Agric Food Chem. 2002 Jun 5;50(12):3549-52.
17. M C S, K S, Kuttan R. Anti-diabetic activity of green tea polyphenols and their role in reducing oxidative stress in experimental diabetes. J Ethnopharmacol. 2002 Nov;83(1-2):109-16.
18. Ahmed S, Rahman A, Hasnain A, Lalonde M, Goldberg VM, Haqqi TM. Green tea polyphenol epigallocatechin-3-gallate inhibits the IL-1 beta-induced activity and expression of cyclooxygenase-2 and nitric oxide synthase-2 in human chondrocytes. Free Radic Biol Med. 2002 Oct 15;33(8):1097-105
19. Gupta SK, Halder N, Srivastava S, Trivedi D, Joshi S, Varma SD. Green tea (Camellia sinensis) protects against selenite-induced oxidative stress in experimental cataractogenesis. Ophthalmic Res. 2002 Jul-Aug;34(4):258-63.
20. Imanishi N, Tuji Y, Katada Y, Maruhashi M, Konosu S, Mantani N, Terasawa K, Ochiai H. Additional inhibitory effect of tea extract on the growth of influenza A and B viruses in MDCK cells. Microbiol Immunol. 2002;46(7):491-4.
21. Weber JM, Ruzindana-Umunyana A, Imbeault L, Sircar S. Inhibition of adenovirus infection and adenain by green tea catechins. Antiviral Res. 2003 Apr;58(2):167-73.
22. Fujiki H, Suganuma M, Imai K, Nakachi K. Green tea: cancer preventive beverage and/or drug. Cancer Lett. 2002 Dec 15;188(1-2):9-13.
23. Yang CS, Chen L, Lee MJ, Balentine D, Kuo MC, Schantz SP. Blood and urine levels of tea catechins after ingestion of different amounts of green tea by human volunteers. Cancer Epidemiol Biomarkers Prev. 1998 Apr;7(4):351-4.
24. Nakagawa K, Okuda S, Miyazawa T. Dose-dependent incorporation of tea catechins, (-)-epigallocatechin-3-gallate and (-)-epigallocatechin, into human plasma. Biosci Biotechnol Biochem. 1997 Dec;61(12):1981-5
25. Chow HH, Cai Y, Alberts DS, Hakim I, Dorr R, Shahi F, Crowell JA, Yang CS, Hara Y. Phase I pharmacokinetic study of tea polyphenols following single-dose administration of epigallocatechin gallate and polyphenon E. Cancer Epidemiol Biomarkers Prev. 2001 Jan;10(1):53-8.
26. Chantre P, Lairon D. Phytomedicine. Recent findings of green tea extract AR25 (Exolise) and its activity for the treatment of obesity. 2002 Jan;9(1):3-8
27. Liao S. The medicinal action of androgens and green tea epigallocatechin gallate. Hong Kong Med J. 2001 Dec;7(4):369-74.
28. Morre DJ, Morre DM, Sun H, Cooper R, Chang J, Janle EM. Tea Catechin Synergies in Inhibition of Cancer Cell Proliferation and of a Cancer Specific Cell Surface Oxidase (ECTO-NOX). Pharmacol Toxicol. 2003 May;92(5):234-41.
29. Kajiya K, Kumazawa S, Nakayama T. Effects of external factors on the interaction of tea catechins with lipid bilayers. Biosci Biotechnol Biochem. 2002 Nov;66(11):2330-5
30. Ohe T, Marutani K, Nakase S. Catechins are not major components responsible for anti-genotoxic effects of tea extracts against nitroarenes. Mutat Res. 2001 Sep 20;496(1-2):75-81