Green tea extract

Green tea helps to burn fat

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

The Swiss weight loss study

After careful examination, 10 healthy young men between the ages of 24 and 26 were selected for the study, whose physique ranged from lean to slightly obese (8-30% body fat) and whose daily food intake was around 35-40% fat (the typical Western diet). The average percentage of body fat is around 20% in healthy young men and 27% in healthy young women. In the course of the ageing process, we lose muscle mass, while the fat percentage increases on average to around 30% and 40% respectively. For the entire period of the study (5 - 6 weeks), a precise dietary plan was followed in order to be able to carry out a standardized weight measurement.

The energy intake consisted of 13% protein, 40% fat and 47% carbohydrates. In addition: The first group received a green tea extract in powder form equivalent to about 4 cups of tea, the second group received the same amount of caffeine, which is said to have fat-burning properties, while the third group received a placebo. All three groups received these additional supplements three times a day (breakfast, lunch and dinner) and were then placed in a so-called respiration room for 24 hours to enable an accurate measurement of energy expenditure.

Green tea burns fat

In comparison with the placebo group, the green tea extract caused a significant increase in energy expenditure, namely around 4%. This may seem small at first, but a small effect that is 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) and thus leads to weight loss. ..." 3 Caffeine, on the other hand, did not show any noticeable increase in comparison with the placebo group, mainly because the amount administered of 150 mg/day was below the limit of extra fat burning possible with this substance (thermogenesis).

Another study

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

The average swimming performance of the rodents was 26 minutes. The animals were then either fed a standard diet or given an additional green tea extract. After 10 weeks of training, there was a clear difference in performance between the two groups of mice. While the animals on a standard diet lasted an average of 33 minutes in the counter-current system due to 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 have shown that the tea extract increases the breakdown of fat in the liver. As a result, more energy is made available for muscle work and the animals can perform at their best over a longer period of time. However, the scientists emphasize that this effect is not achieved by a single dose of the extract, but requires regular use. It is thought that long-term use could lead to a metabolic change that increases fat burning and reduces carbohydrate burning.

And green tea can even help with seriously injured muscles. Duchenn's muscular atrophy, for example, is a functional disorder characterized by muscle death caused by a lack of a protein called dystrophin. A study has now investigated whether the antioxidant components of green tea can delay muscle tissue death in mice with muscular dystrophy. For four weeks, from the day of birth, 0.01 or 0.05 percent green tea extract was added to the diet of the small rodents. This addition significantly reduced tissue death (necrosis) in the fast-switch fibers in a dose-dependent manner - however, it showed no effect on the slow-switch fibers in the study. To achieve a positive effect in humans, one should drink around seven cups of green tea a day.

Thermogenesis

Thermogenesis is the term used to describe the development of heat, particularly 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 mainly via 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 is therefore the way in which calories are "burned". It could be that the effect of the green tea extract is partly due to the caffeine content 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, as 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 that is able to protect 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 lung. No other food supplement can claim this.

Although there are many chemical substances in green tea, one of them stands out and is considered by some scientists to be the most promising substance ever discovered in the fight against cancer. It is epigallocatechin gallate (EGCG) and belongs to the class of catechins. These are members of a larger group, the polyphenols, which in turn belong to an even larger group, the flavonoids. You have probably heard a lot about flavonoids. These are the colorful pigment substances that we know from so many fruits, vegetables and teas. They are known to us for their powerful antioxidant effects 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

Of all the catechins in green tea, EGCG is by far the most pharmacologically active and effective substance and, fortunately, contains the largest amount compared to over half of all the other active ingredients. In the Swiss weight loss study mentioned above, the dose of green tea extract was 375 mg/day 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 in terms of protecting DNA from damage by free radicals is 100 times stronger than that of vitamin C and 25 times greater than that of vitamin E. In addition, EGCG is able to stop the reproduction of cancer cells and trigger a natural process of programmed cell death, known as apoptosis. EGCG also inhibits the production of an enzyme called urokinase, which is required for the growth of cancer cells.

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

Green tea also combats heart disease

Meanwhile, green tea also plays a role in protecting against heart disease.7 A study carried out with rodents showed that green tea is able to reduce the amount of lipids (fats) such as cholesterol, particularly LDL (the "bad", "low-density" cholesterol) in the blood. In addition, it blocks the oxidation of LDL, which reduces the tendency to arterial deposits (arteriosclerosis) and thus to possible subsequent heart attacks. At the same time, it contributes to an increase in HDL, the "good" cholesterol, and reduces the blood sugar level and the proportion of triglycerides, which could possibly reverse the effects of so-called 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-lying leaves of the tea plant. These are steamed, rolled and dried immediately after cutting and then prepared for the commercial tea product. The better-known black tea is obtained from the same green leaves, except that they 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 in which a number of valuable polyphenols in the tea leaves are converted and broken down into less effective substances by enzymatic action, with the result that some of the medicinal value of the tea is lost. 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

Tea derives its astringent or astringent properties from the tannins it contains (as found in red wine) and its stimulating properties from its 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 ephedra plant. Caffeine and ephedrine not only have a stimulating effect in terms of thermogenesis, they also suppress the appetite. The fact that they promote fat loss but leave muscle mass untouched is particularly advantageous. Add to this already potent combination the antioxidant capacity of the polyphenol EGCG and you have a really powerful trio.

Requirements in sport

Take approx. 250-500mg of green tea extract standardized to 50% EGCG once or twice a day on an empty stomach.

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