How much caffeine is in green tea. Does green tea have caffeine and how can it affect your health?

Have you ever wondered does tea have caffeine? It turns out that there is, and in fairly large quantities. It’s worth immediately reassuring lovers of the No. 1 drink in the world: despite the presence of caffeine (more precisely, theine) in tea leaves, its effect on human body several times milder than the effect of caffeine in coffee beans. This happens due to the fact that in tea the theine is not in pure form, but in a bound state.

Hence the difference in the effect that tea and coffee have on the body. The caffeine content in a cup of coffee is about 80-120 mg, and in a cup of tea 30-60 mg. Coffee begins to act on the body almost instantly (high caffeine content in its pure form), but the effect of vigor and energy from coffee wears off very quickly. But tea caffeine does not begin to act from the first sip; the body needs time to absorb it. It is thanks to this that the action of theine is much longer and softer. The effect may last for several hours. In addition, we must not forget that the effect of tea is based not only on the effect of theine on the body. Tea leaves contain hundreds of substances beneficial to the human body, including vitamins, minerals, trace elements and even essential oils. The beauty of the tea leaf is that almost half of this rich bouquet can dissolve in water.

Does tea have caffeine and in what quantities?

As you can see, to the question does tea have caffeine The answer is more than clear - there is caffeine, and in considerable quantities. That is why excessive tea consumption should be treated with caution. Although not to the same extent as drinking coffee, it won’t hurt anyone to regulate the daily dose of caffeine. Whatever one may say, caffeine is an alkaloid, and an overdose of it in the body is extremely dangerous. True, to achieve an overdose of tea caffeine, you need to drink at least 20-30 cups of tea a day, but this possibility still exists and should not be discounted. Especially information about whether there is caffeine in tea should be relevant for pregnant and nursing mothers and people with heart disease. Doctors' recommendations are very ambiguous. Some of them claim that tea cannot cause any harm to the body. The other part warns of a possible negative impact. Looking at both of them, we can say one thing - in matters related to tea drinking, you need to stick to the golden mean. The beneficial effects of two to three cups of tea a day on the body more than offset the negative effects of caffeine.

This publication was prepared by Mayo Clinic staff.

If you're like most people, caffeine is part of your everyday life. But do you know the amount of caffeine contained in your favorite drink?

You might want to know how much caffeine you consume per day, especially if you're experiencing headaches, restlessness, or anxiety. If your caffeine intake exceeds 500 milligrams (mg) per day, you may want to consider cutting back.

With growing popularity energy drinks, many parents worry about the amount of caffeine their children are getting. The American Academy of Pediatrics recommends that teenagers consume no more than 100 mg of caffeine per day. For children younger age You should not regularly drink drinks containing caffeine.

Table of caffeine content in tea and coffee

Study the tables presented in the article to calculate the amount of caffeine you receive. Please note that the data in the tables is indicative only. The concentration and caffeine content of the same type of coffee may differ due to different roasting, grinding or brewing times. The caffeine content of tea also depends on the brewing time.

How much caffeine is in a cup of coffee?

How much caffeine is in tea?

Caffeine content in carbonated drinks

Caffeine in energy drinks

Caffeine in other products

To prepare the review, data from periodicals were used: Journal of Food Science, Pediatrics, Journal of Analytical Toxicology, Starbucks, Food and Chemical Toxicology, Keurig, Food and Drug Administration. In addition, information from the US National Food Database and data from food and beverage manufacturers was used.

Based on materials from: http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/caffeine/art-20049372

This publication was prepared by Mayo Clinic staff. Caffeine Content of Beverages: Introduction If you are like most people, caffeine is part of your daily life. But do you know the amount of caffeine contained in your favorite drink? You might want to know how much caffeine you consume per day, especially if you have headaches,...

Irina Mishina

Contrary to popular belief, tea contains even more caffeine than coffee. While a shot of espresso made from 100% Arabica coffee contains only 1.2% caffeine, a cup of high-quality Assam coffee can contain as much as 4%. True, the caffeine contained in dry leaf tea is never completely extracted into the infusion, which means that its actual content in the finished tea will always be slightly lower.

In addition, tea caffeine has a more gentle effect on the heart and nervous system than coffee caffeine. This is due to the fact that in tea this alkaloid is not present in pure form, but in combination with tannin. Together, caffeine and tannin form a new substance (theine), which is rather slowly absorbed into the blood and quickly eliminated from the body. Therefore, it is impossible to be poisoned by theine, even if you drink strong tea in very large quantities (up to 12 cups per day).

In addition, the caffeine content largely depends on the place where a particular type of tea is grown: on the climate of the area, on the characteristics of the soil (for example, on the zinc content in it) and on the altitude above sea level. The higher the tea plantation is located, the colder the air, which means the slower the tea leaves grow and the more caffeine they contain. Bright sunlight also promotes the growth of caffeine-rich tea leaves, which is why some teas are specifically grown in the shade.

Another important factor affecting the caffeine content is the degree of fermentation of the tea leaves. The lower it is, the more caffeine the tea contains. From this we can conclude that the most “caffeinated” varieties are white teas, green teas and oolongs. But in reality, everything is not so simple. Not only the variety matters, but also the method of preparing tea, including the temperature of the water when brewing. The hotter the water, the more caffeine is released. And because unfermented and lightly fermented teas are brewed with warm rather than hot water, they contain less caffeine when finished than full-bodied black tea.

The amount of caffeine also depends on the time the tea is brewed - the longer it is, the more caffeine will have time to be released into the cup. However, if brewed for too long, tea phenol, lipids and essential oils contained in tea begin to spontaneously oxidize, which negates all the benefits of theine and spoils the taste and aroma of the drink. The unpleasant bitterness that occurs during prolonged brewing is most often caused not by the high caffeine content, as many believe, but by the presence of harmful substances in the drink. Therefore, the tea brewing time should in no case exceed 5-6 minutes.

Tea strength and caffeine

It is widely believed that the strength and astringency of tea depend primarily on how much caffeine it contains. In fact, the strength of tea is not determined by caffeine at all, and these concepts are practically unrelated. For example, varieties of black Ceylon tea, which are distinguished by their strength and richness, contain less caffeine than “weak” and mild Chinese varieties. The dark color of the drink also does not indicate a high caffeine content.

An indicator of the strength of black tea is the fullness of its taste and aroma, the astringency of the infusion and the appearance on the surface of the cooled drink of the so-called “tea cream” - a thin film of brownish-orange color containing a mixture of caffeine and catechins. The brighter it is, the higher the quality of black tea. “Cream” does not form on the surface of green and white tea.

Is caffeine in tea harmful or beneficial?

Many people think that strong tea is harmful to the body. In fact, it is much worse to drink a weak tea infusion, which contains few nutrients and a lot of hot water. Whether tea will cause more harm or benefit depends not so much on the strength of the drink or on the caffeine content in it, but on the quality of the tea itself and whether it was brewed correctly.

Many people drink tea constantly and in considerable quantities. For most, a cup of strong tea in the morning is sacred. When wondering whether there is caffeine in tea, you first need to pay attention to the effect of this drink. A cup of aromatic and strong tea gives vitality, saturates with energy and increases performance.

Caffeine is an alkaloid produced by many representatives of the plant world to protect against pests. This substance has the property of stimulating the nervous system and accelerating the functioning of the cardiovascular system.

This manifests itself in the body like this:

• heartbeat accelerates;
• blood pressure increases;
• cerebral circulation improves;
• the secretion of gastric juice is stimulated;
• blood vessels narrow;
• breathing quickens;
• urination increases;
• mood improves;
• drowsiness goes away;
• working capacity increases.

This effect is not dangerous for a healthy body. But for easily excitable people and people with heart disease, it is better to avoid drinking caffeine-containing drinks.

So, does tea have caffeine? The answer is unequivocal - yes. However, the amount of caffeine in green tea is often about the same as in strongly brewed black tea. Previously, theine, a substance with a similar effect, was found in tea leaves. Then the researchers concluded that these components are absolutely identical, so now they are used as synonyms. But still, theine is a little different from its brother: it does not accumulate in the internal organs and does not cause a caffeine overdose.

It must be remembered that the maximum permissible dose of caffeine is 1000 mg, a single dose is 2.5 times less.

Exceeding these parameters negatively affects the functioning of the heart and can even lead to death. The maximum content of the substance in the blood is observed 40–60 minutes after ingestion, the main part is excreted within 6–12 hours.

Where is there more caffeine in tea or coffee?

The drinks under discussion may well compete with each other in terms of the content of this component.

In dried raw materials for tea production, the concentration of theine is higher than in coffee beans, but during the brewing process this ratio changes. For example, in a cup of instant coffee drink there is exactly as much of it as in the same amount of green tea, which was brewed for at least 5 minutes.

But you need to take into account that coffee is rarely drunk in more than one small cup with a capacity of 30 ml. Many people drink tea in large cups of 200–230 ml, and even in several doses. Therefore, during such a tea party you can get a decent dose of this substance.

Brewing time is also an important parameter. A cup of well-brewed tea will contain much more theine than the same amount of weak coffee with milk.

Table: how much caffeine is in tea

Many people are interested in specific figures about how much caffeine is in black tea and its other types. Interestingly, this depends on the specific varieties, as well as the brewing time of the drink - the longer it is brewed, the more theine will be extracted from the leaves.

Also, much depends on the time of collection of leaves, production technology and the quality of the final product. For example, the earlier the raw material is collected, the less theine it contains. In small leaves the concentration of this substance is much higher.

As a rule, the maximum concentration of theine is found in strong black or green tea, and the minimum in milk oolongs. The variety also plays an important role. Tasty and light white tea "Bai Hao Yin Zhen" contains a higher percentage of theine than the dark and rich "Shou Mei".

Which tea has no alkaloid at all?

The maximum concentration of theine is in the upper leaves. Large leaves on the lower branches contain less than 1 - 2%. Elite varieties are prepared from the upper leaves, and the cheapest ones from the lower leaves.

Therefore, the cheaper the tea, the less theine it contains.

Among non-caffeine drinks, teas from other plants can be distinguished - fireweed, chamomile, hibiscus, linden, mint, lemon balm, thyme, and other herbal infusions. You can reduce the amount of theine in tea like this: add some other ingredients to it - a slice of lemon, some berries, 1 tsp. chamomile or thyme.

Caffeine in decaffeinated tea

Decaffeinated tea is designated with a "D". But this does not mean that products with such labeling do not contain this substance at all. A small amount remains of the original volume - 3%, but caffeine is still present in such drinks. Of course, this amount is so insignificant that it is unlikely to cause any harm, but you should pay attention to the methods of decaffeination - not all of them are considered safe for human health.

Decaffeination methods are varied:

• Use of carbon dioxide. The steam-treated raw materials are placed in a special container with CO2 under a pressure of 100–250 atmospheres and kept for at least 9 hours. When the pressure is removed, the gas evaporates, and the caffeine is easily removed by filtration. This method is non-toxic and allows you to fully preserve the taste of the tea. However, it is rarely used, as it requires large investments.
• Use of ethyl acetate. This substance can be organic (derived from fruits or vegetables) or synthetic. First, the raw materials are treated with steam, and then with ethyl acetate for at least 10 hours. After this, the raw materials are further processed to remove residual solvent. It is slightly toxic, but has a strong effect on taste and smell.
• Use of methyl chloride. This method cannot be called safe. The toxic chemical is quite dangerous, so companies selling such tea do not advertise their methods of processing raw materials.

Tea leaves contain a lot of complex chemical compounds, and during any processing a significant part of them is lost. It is difficult to make sure that caffeine is absent and the remaining components remain in their original volume.

You cannot decaffeine tea yourself. It is believed that draining the first water helps remove most of the substance. However, this technology only works with crushed tea leaves. In addition, during this procedure the drink loses its taste and aromatic properties. Large leaf varieties, along with a pleasant taste and aroma, retain a high theine content for a long time.

Decaffeinated drinks do not have a rich taste. Therefore, it is better to purchase varieties with fruit additives to enjoy the taste of tea. People suffering from heart and vascular diseases can drink this tea without restrictions - up to 8 glasses per day.

Based on the above, we can come to the conclusion that the caffeine content in tea is quite significant. However, when used wisely, the drink brings many benefits, so choose a quality product and drink without fanaticism, enjoying every cup.

Billions of people on planet Earth start their morning with a cup of tea. Why? Of course, to shake off the sleepy shackles and cheerfully enter the coming day. And due to what? Of course, due to the influence of the main alkaloid of tea - caffeine. The more caffeine in tea, the more morning energy we get.

But which tea – green or black tea – has more caffeine? Many people believe that black tea is stronger and therefore more caffeinated. Is this true?

To find out which type of tea is stronger - green or black, public organization"EXPERT" for the first time in Ukraine conducted a laboratory comparison between green and black tea. A sort of fight in the ring between the “Blacks” and the “Greens”. Who wins?
We examined 34 tea samples and determined:

Green tea has more caffeine!

In our study it was green tea confidently took all the top positions in the rating of caffeine content in tea. We even gave the “blacks” a head start - out of 34 samples, there were 21 “fighters” in their team, and 13 in the “green” team. The Greens still won. Of the 13 samples of green teas, 8 were leaders in both total caffeine content and caffeine content per 1 bag. This clearly indicates a higher caffeine content compared to black tea. Thus, the caffeine content in 1 bag of green tea was, as a rule, more than 71 mg, and in black tea 71 mg is the limit.

The group of green teas without flavors turned out to be the most caffeine-containing. There, the caffeine content in most teas was more than 80 mg. We emphasize that all the figures given are for a cup of tea. Not dry tea leaves, but just enough for a cup of tea. At the same time, the weight of the bags was also taken into account - after all, there are bags of 2 grams, and there are also 1.5 grams. Everything was meticulously taken into account.

So, 5 different types of tea were studied: black, green, black with lemon, green with jasmine, black with bergamot. HERITAGE tea (green, unflavored) had the highest caffeine content among the 34 samples, with 85 mg per cup of tea. The lowest caffeine content among the 34 samples was found in DILMAH tea (black, lemon flavored) at 40 mg.

So, we found out where there is usually more caffeine. This is an important study because... Many mothers believe that green tea can be given to young children, thinking that it is weak. Caffeine is not recommended for children under two years of age! Moreover, in the strongest tea, as we found out, green tea.

So what is this substance - caffeine and how does it actually affect our body?

Known in chemistry as 1,3,7-trimethylxanthine, caffeine is a type of methylxanthine compound found in more than 60 plant foods, but is found in sufficient quantities only in: tea leaves and coffee beans. At the same time, the caffeine in tea is associated with tannin, so its effect is milder than the effect of caffeine in coffee. This has its positive side - tea does not cause addiction, as coffee often does.

From a medical point of view, caffeine is a classic psychomotor stimulant. It has the property of stimulating the nervous system, reducing the feeling of fatigue, increasing mental activity, and driving away sleep.

The stimulating effect of caffeine on the central nervous system is associated with its ability to block an enzyme (phosphodiesterase), which limits the conduction (transmission) of nerve impulses to the cell. As a result, any exciting signal begins to act more strongly on nerve cells. At the same time, the blood vessels of the brain dilate.

Simultaneously with the central nervous system caffeine also stimulates the autonomic (innervating) internal organs) system. The blood vessels of the skeletal muscles dilate.

The frequency and strength of heart contractions increase. Blood pressure increases, but for a healthy person and with safe doses of caffeine it is not high, because Although caffeine stimulates the release of vasoconstrictor factors, it also stimulates the release of vasodilators. However, for people with chronically high blood pressure, caffeine is contraindicated.

Caffeine stimulates thermogenesis. Thermogenesis is the process by which the body burns calories instead of storing them as body fat. This happens as follows. Caffeine reduces blood clotting and activates tissue oxidation processes. At the same time, glycogen breakdown increases. Its reserves in the liver and muscles decrease. Increased breakdown of glycogen leads to increased blood sugar levels. Therefore, caffeine has the ability to destroy subcutaneous neutral fat and increase the content of fatty acids in the blood. An increase in blood sugar and fatty acids is one of the reasons for the feeling of vigor and energy.

Danish scientists examined normal-weight volunteers and found that the effects of caffeine remained noticeable more than two and a half hours after consumption. Caffeine-stimulated calorie burning occurs even faster during exercise. Caffeine also has the property of increasing the body's ability to withstand exercise. Canadian scientists recently discovered that even moderate amounts of caffeine make exercise much more effective. Caffeine helps convert fat into fuel for muscles, increasing their performance.

It is fatty acids that enter the blood that cause increased heat transfer and an increase in body temperature. Thanks to its ability to mobilize sugar from glycogen depots and fatty acids from the subcutaneous fat layer, tea eliminates the feeling of hunger and has a warming effect. Cold tolerance improves.

So, caffeine has certain effects on the body. This effect depends on the dose of this substance that enters the body: in small quantities it tones, but in large quantities it has a negative effect on the human body. Therefore, when asked whether caffeine is harmful, doctors answer unequivocally: for people with certain diseases it is harmful, for healthy people - in certain doses it is harmless and even beneficial.

First, about those for whom caffeine in any drink - coffee or tea - is contraindicated. Caffeine-containing drinks should not be consumed by people with persistently high blood pressure, as well as those suffering from vascular diseases and atherosclerosis. Due to the increased acidity that occurs after taking caffeine, it is not recommended for those who suffer from gastritis, peptic ulcer stomach or duodenum.

Now about those who are advised to limit themselves to tea and coffee. Doctors recommend that pregnant and breastfeeding women limit themselves and drink no more than two cups of tea or 1 cup of coffee per day, since the embryo absorbs caffeine, but eliminates it more slowly than the adult body. Children can drink tea no earlier than 2 years old and in a dose 3 times less than the norm for an adult.

Caffeine in a reasonable amount will not harm a healthy person and is even beneficial. But what is meant by a reasonable dose?

Doctors consider 100-200 milligrams of caffeine to be a safe single dose. The maximum permissible daily dose is 1000 milligrams of caffeine (1000 milligrams = 1 gram).

As we can see from a study conducted by the public organization "EXPERT", a cup of tea contains a maximum of 85 milligrams of caffeine. Accordingly, 12 cups of tea per day will not harm you. But there is no need for so much tea. Therefore, 2-3 cups that we usually drink per day will only bring benefits.

public organization "EXPERT". 2007