What are the side effects of green tea. Side effects of green tea

Green tea is considered very beneficial for health. This is true, but in everything you need to know the measure: it is not recommended to drink more than 5 cups a day.

In addition, like all teas, green tea contains caffeine. If you have a caffeine intolerance, limit yourself to 2 cups.

Excessive caffeine intake can cause or exacerbate a range of health problems, including:

Disorders of the stomach.

Therefore, the Japanese and Chinese never drink green tea on an empty stomach.

Iron deficiency and anemia.

Green tea reduces absorption gland from food. Iron deficiency can lead to disease (such as anemia).

Very high dose green tea can be deadly!

Lethal dose caffeine in green tea is estimated at 10-14 g (150-200 mg/kg).

Headache.

Research shows that caffeine- a risk factor in the occurrence of chronic daily headaches.

Sleep disturbances, nervousness and anxiety.

Caffeine obviously affects anxiety and sleep, although the effect depends on individual sensitivity to methylxanthine. It blocks sleep-inducing substances in the brain and increases the production of adrenaline.

Irregular or fast heartbeat

Caffeine in green tea can cause cardiac arrhythmias. In addition, it stimulates the heart muscles to contract.

Vomit.

Because the caffeine affects the flow of blood through the esophagus, the alternating contraction and relaxation of the muscles of the esophagus can cause nausea.

Diarrhea.

Caffeine has a laxative effect. It promotes peristalsis (the movement of food through the digestive system) and stimulates the muscles in the colon.

Muscle tremor.

Caffeine causes contractions skeletal muscle, negatively affecting the channels calcium ions in cells.

Heartburn.

Caffeine increases production gastric juice. This can lead to heartburn.

Dizziness.

caffeine can reduce blood flow to the brain which leads to dizziness and motion sickness.

Tinnitus.

Caffeine can aggravate tinnitus(tinnitus).

Convulsions.

Caffeine stimulates the central nervous system, activating neurons, which can cause convulsions if consumed in excess.

Bleeding.

The caffeine in green tea may increase the risk of bleeding.

Diabetes.

The caffeine in green tea can affect blood sugar levels. If you are a diabetic and drink green tea, watch your sugar levels.

Glaucoma.

Green tea increases intraocular pressure. This happens 30 minutes after consumption and lasts at least 90 minutes.

High pressure.

The caffeine in green tea can increase blood pressure. However, this effect is not observed in those who drink green tea (or other caffeinated drinks) regularly.

Liver diseases.

Green tea extract may exacerbate liver failure by promoting the accumulation of caffeine in the blood.

Osteoporosis.

Green tea may increase calcium leached out in the urine, which is bad for bone health and can lead to osteoporosis, especially in predisposed people.

Limit your caffeine intake to 300 mg per day (approximately 2-3 cups of green tea).

Risk for pregnant women and infants.

Green tea contains caffeine, catechins and tannins. All these substances are dangerous during pregnancy.

Nutritional absorption in children.

The tannins in green tea can interfere with the absorption of proteins and fats in children. In addition, caffeine can lead to overstimulation.

Nikita Skorobogatov

Here we will give some features of the use of both black and green tea, as well as the rules that you need to follow when drinking tea if you are looking after your health.

What are the benefits of green tea.

Green tea preparations have a diuretic effect, but due to the stimulating effect, it is not recommended to use it as a diuretic.

Green tea is one of the best means from fatigue. Green tea infusion is used as an antimicrobial agent for dysentery. This tea is a means of preventing urolithiasis and cholelithiasis. Both red and green as well as black teas support the tone of the body. In individual tea consumption can affect the appetite - both by stoking and satisfying the feeling of hunger.

Thanks to the content of vitamin C, green tea helps to cope with many oncological diseases. Vitamin P contained in green tea makes the walls of blood vessels stronger and more elastic. All these beneficial properties also apply to black or red tea. Beneficial features green tea is due to the fact that its composition contains a large number of various bioactive substances, trace elements and vitamins.

Fun fact: red or black tea in Soviet times was used extremely in an unusual way. Women of fashion did without solariums to make the skin swarthy. To do this, they poured some water into black tea, put it on fire, bringing it to a boil, and then insisted, waiting for the liquid to cool. The skin was rubbed with this infusion twice a day. Tanning without sunbathing is ready.

However, some people should carefully drink tea so as not to harm themselves.

Tea, whether black, green, red or pu-erh, is certainly extremely beneficial for health.

1. Pregnant women

Any tea contains a certain amount of caffeine, which, by stimulating the fetus, negatively affects its development. It is often heard that since there is less caffeine in black (red) tea, it is not harmful to pregnant women. But, in reality, black and green tea do not differ much in this indicator. According to Japanese researchers, five cups of tea drunk a day contains such an amount of caffeine that can lead to significant underweight in an infant. In addition, caffeine causes an increase in heart rate and increases urination, which increases the burden on the heart and kidneys, and thus increases the likelihood of developing toxicosis.

2. Suffering from stomach problems

Although tea, especially pu-erh, promotes digestion, but those suffering from stomach ulcers and duodenum, as well as increased acidity in the stomach, its use, both green and black, should be avoided. A healthy stomach contains a compound of phosphoric acid, which reduces the secretion of gastric acid in the cells of the stomach wall, but theophylline found in tea can suppress the function of this compound, resulting in excess stomach acid, and hyperacidity gastric juice disrupts the functionality of the stomach and contributes to the formation of ulcers. Therefore, those who have stomach problems, and, moreover, those who already have, should stop drinking both black and green, and other types of tea, since this will remove the stimulation of gastric acid secretion characteristic of tea and can be harmful.

3. Suffering from atherosclerosis and hypertension

Patients with a similar diagnosis should also stop drinking black and strongly brewed green tea. This is due to the fact that tea contains theophylline and caffeine, which have an exciting effect on the central nervous system. And when the cerebral cortex enters a state of excitation, blood vessels The brain narrows, which is harmful for those suffering from atherosclerosis and can cause blood clots to form in the brain.

4. Insomniacs

Insomnia can have a variety of causes, but regardless of its causes, you should not drink green or black (even weak and sweet) tea - due to the stimulating effect of caffeine. Just one cup of tea before bed puts the central nervous system and brain in a state of excitement, the pulse quickens, blood flow accelerates, it becomes almost impossible to fall asleep. For getting maximum benefit and not causing harm from drinking tea, it is recommended to finish tea drinking a couple of hours before bedtime. For the elderly, drinking tea in the morning is recommended.

5. Patients with fever

The heat is accompanied by the expansion of superficial blood vessels and increased sweating, therefore heat leads to excessive consumption of water, dielectrics and nutrients from which thirst arises. It is generally accepted that hot black tea quenches thirst well, and therefore is useful for elevated temperature. But this is very far from reality. Recently, British pharmacologists have found that tea not only does not benefit those suffering from fever, but, on the contrary, theophylline, which is especially abundant in green tea, increases body temperature. Theophylline, present in both black and green tea, is also a diuretic and therefore renders any antipyretic drugs ineffective.

In addition, you should pay attention to the following factors when drinking tea:

scalding tea
Too much hot tea strongly stimulates the throat, esophagus and stomach, and can also burn the mucous membrane of the mouth, which will prevent you from fully enjoying the wonderful taste of tea. The tea temperature should not exceed +56°.

Cold tea
While moderately hot tea gives vigor, makes consciousness and vision clear, cold tea has negative side effects - stagnation of cold and accumulation of sputum.

Strong tea.
High content of theine and caffeine in strong tea can cause headaches and insomnia.

Long brewing tea.
If tea is brewed for too long, tea phenol, lipids, essential oils begin to spontaneously oxidize, which not only deprives the tea of ​​transparency, palatability and aroma, but also significantly reduces nutritional value tea due to the oxidation of vitamins C and P contained in tea leaves, as well as other valuable substances.

Multiple brewing.
The number of brews is determined by the method of brewing and the quality of the tea. When brewing tea "in European style", when each brew is infused for 5-10 minutes, usually after the third or fourth brew, there is little left in the tea leaves. Experiments show that the first infusion draws approximately 50% useful substances from tea leaves, the second - 30%, the third - only about 10%, and the fourth adds another 1-3%. If you continue to brew tea further, then the infusion may begin to come out harmful substances contained in tea leaves in very low large quantities, since they are the last to enter the infusion. When brewing tea using the Ping Cha method, when a lot of tea is placed in a small volume and infused a little (a few seconds), the tea withstands 5-8 brews, some collection varieties 10-15 brews.

Tea before meals.
Drinking tea just before a meal thins saliva, making food tasteless, and may temporarily decrease protein absorption. digestive organs. Therefore, tea should be drunk no later than 20-30 minutes before meals.

Tea after meals.
The tannin content in tea can cause protein and iron to harden, making them less absorbable. If you want to drink tea after a meal, wait 20-30 minutes.

tea on empty stomach.
If you drink strong tea on an empty stomach, cold nature tea, penetrating inside, can cool the spleen and stomach", which can cause discomfort.

Drinking medicine with tea.
The tannins contained in tea break down to form tannin, from which many medicines precipitate and are poorly absorbed. That is why the Chinese say that tea destroys medicines.

Yesterday's tea.
Tea that has stood for a day not only loses vitamins, but due to the high content of protein and sugars, it becomes an ideal breeding ground for bacteria. If the tea has not spoiled, it is quite possible to use it in medicinal purposes but as an external agent. So, tea that has been infused for a day is rich in acids and fluorine, which prevent bleeding from capillaries, so yesterday's tea helps with inflammation of the oral cavity, pain in the tongue, eczema, bleeding gums, superficial skin lesions, abscesses.
Washing the eyes with yesterday's tea helps to reduce discomfort when manifested in the proteins of blood vessels and after tears, and rinsing the mouth in the morning, before brushing the teeth and after eating, not only leaves a feeling of freshness, but also strengthens the teeth.

Note: The information given is quite general and varies depending on the type of tea and the conditions of its brewing. So, in particular, with regard to the number of brews of one serving of tea, then good varieties teas can withstand 10 or more infusions, retaining color, aroma and nutritional qualities; brewing water temperature tea leaf- also the indicator is changeable, it varies from 65 degrees for light teas - green and white, up to 95-100 degrees for black and red teas...

frequency of tea drinking.

No matter how useful tea is, do not forget about moderation. Overuse tea means increased load on the heart and kidneys. Strong tea leads to excitation of the brain, rapid heartbeat, frequent urination, insomnia. caffeine in large doses, as shown by recent medical studies, contributes to the occurrence of certain diseases. Therefore, with tea you should know when to stop.
On average, 4-5 cups of not very strong tea during the day are beneficial, especially for a middle-aged person. Some cannot do without strong tea, because otherwise they do not feel the taste. In this case, you should limit yourself to 2-3 cups, at the rate of 3 grams of tea leaves per cup, so 5-10 grams of tea comes out per day. Tea is better to drink a little, but often and always freshly brewed. Of course, you should not drink tea at bedtime. It is useful for older people to drink just in the evening boiled water, best boiled shortly before and then cooled to room temperature.

The Chinese drink tea no more than three times a day.

On the intoxicating effect of tea.

"Tea intoxication" can be caused by tea in excessive amounts or improperly prepared tea. The harm from such intoxication can hardly be called too strong, but you still should not abuse tea. Tea on an empty stomach, tea on a full stomach, a shock dose of tea for an unaccustomed organism can lead to symptoms such as restlessness, dizziness, impotence in the limbs, discomfort in the stomach, unsteady standing, hunger. Concerning different varieties and ways of drinking tea, the greatest danger is tea on an empty stomach. Most susceptible tea intoxication weakened people with emptiness in the kidneys. When the described symptoms appear, you should immediately eat something - either honey or fruit.

Tea and alcohol.

Tea is not compatible with alcohol. Tea after alcohol adversely affects the kidneys. Theophylline, found in tea, speeds up the process of urine production in the kidneys, which leads to the fact that undigested urine can get into them. acetaldehyde, which is highly stimulating harmful effect on the kidneys, in some cases posing a threat to life. Alcoholic beverages should not be mixed with tea, and especially with strong tea. According to the doctrine of yin-yang, alcohol has spicy taste, which primarily goes to the lungs, the lungs correspond to the skin and interact with the large intestine. As for tea, it promotes the rise of yang energy and stimulates blood circulation, it tastes bitter and belongs to yang. When tea is drunk after alcoholic drinks, it has a stimulating effect on the kidneys, the kidneys govern water, water gives rise to warmth, as a result of which cold stasis occurs, which leads to cloudy urine, excessive dryness of the feces, and impotence. In the famous treatise of Li Shi-zhen, “Ben-cao gan-mu” it is written: “Tea after wine harms the kidneys, the lower back and hips are filled with heaviness, the bladder becomes cold and sore, and in addition, phlegm accumulates, and swelling appears from the drunk liquid” .

Modern medicine complements Chinese teachings. First, the alcohol in alcohol has a strong stimulating effect on the heart and blood vessels, and tea has a similar effect. Therefore, when the action of tea is added to the action of alcohol, the heart receives even stronger stimulation, which does not bode well for people with weakened heart function.
Secondly, tea after even very light alcohol negatively affects the kidneys. So most of the alcohol is converted first in the liver to acetaldehyde, then to acetic acid, which decomposes into carbon dioxide and water, then is excreted through the kidneys from the body. Theophylline found in tea speeds up the process of urine production in the kidneys, which leads to the fact that not yet broken down acetaldehyde can get into them, which has a highly stimulating, harmful effect on the kidneys, in some cases life-threatening.
Therefore, alcoholic beverages (even low-grade beer) should not be mixed with tea. It is best to eat fruits - sweet tangerines, pears, apples, or, even better, drink watermelon juice. Will help in a pinch fruit juice or sweetened water. Chinese pharmacology also recommends a decoction of kudzu liana flowers or a decoction of kudzu root and mung beans for quick sobering up. If intoxication is characterized by such symptoms as slow breathing, unconsciousness, weakening of the pulse, cold sweat on the skin, you should consult a doctor as soon as possible.

Is it good for children to drink tea?

It is generally accepted that tea is harmful to children, as it has a too pronounced stimulating effect. Parents are also afraid that tea can damage the spleen and stomach, which are very tender in childhood. In fact, there are no grounds for these fears.
Tea contains phenolic derivatives, caffeine, vitamins, protein, sugars, aromatic compounds, as well as zinc and fluorine, necessary for the development child's body. Therefore, tea, subject to moderation, is undoubtedly useful for children. In general, you should not give children more than 2-3 small cups a day, do not brew tea strongly, and even more so give it to drink in the evening. Also, tea should be warm, not hot or cold.

Little children often have an increased appetite and easily overeat. In this case, tea will help, as it dissolves fats, improves intestinal motility and increases the separation of digestive secretions. The vitamins and methionine contained in the tea effectively regulate fat metabolism and reduce the feeling of discomfort after a fat meat food. Tea also removes the "fire", from the excess of which children often suffer. The symptom of fire (according to traditional Chinese medicine) is dryness of the feces, which leads to difficult defecation. To get rid of this problem, some try to give honey and bananas to children, but this only gives a one-time effect. The best way elimination of "fire" - regular consumption of tea, which, according to traditional Chinese medicine, is "bitter and cold", and therefore removes fire and heat. The people describe the effect of tea on the body as follows: "at the top it clears the head and eyesight, in the middle it improves the digestion of food, and at the bottom it improves urination and defecation," and these words are undoubtedly justified. In addition, as you know, microelements are necessary for the growth of bones, teeth, hair, nails, and the fluorine content in tea, especially in green tea, is much higher than in other plants. Therefore, the consumption of tea not only strengthens the bones, but also prevents tooth decay.

Of course, children, especially toddlers, should not drink a lot of tea, and strong or iced tea should also be avoided. A large amount of tea increases the water content in the body, thereby increasing the load on the heart and kidneys. Strong tea stimulates the child's central nervous system, increases the heart rate, increases the urge to urinate, and can cause insomnia. In a growing child, all body systems are not yet mature, and therefore regular overexcitation, and even more so insomnia, leads to an overuse of nutrients and negatively affects the growth process. Do not infuse tea for too long, as this will release too much tannin into the solution, and tea with a high concentration of tannin can lead to compression of the mucous membrane of the digestive tract. Connecting with food proteins, tannin gives a protein of tannic acid, which, precipitating, suppresses appetite, negatively affects digestion and absorption of food. In addition, the stronger the tea is brewed, the less vitamin B1 it contains, and the worse, therefore, iron is absorbed. So, a little weak tea will do the kids good, but strong tea, and even in large quantities, will only bring harm.

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Throughout the ages, people's food preferences have changed, but tea has remained an integral part of the diet of each generation. The homeland of wild tea bushes is Ancient China, where for the first time they thought about the benefits of brewed and dried leaves. The spread of green tea occurred gradually as it gained popularity. But initially black tea did not exist. It appeared due to fermentation: the Chinese noticed that damp green tea turns black after repeated drying.

Many people cannot imagine the beginning of their day without fragrant and strong drink, in almost all offices, employees have a tea break. But this drink not only invigorates, warms in winter and refreshes in the heat. Black tea can be safely attributed to medicinal plants for his positive impact on the human body.

Effect on the nervous system

Black tea contains caffeine, which mild form acts on the human nervous system. Cup in the morning fragrant drink will help get rid of drowsiness, increase concentration capabilities, and the duration of this effect will last until lunch. Such a mild effect on the nervous system is possible due to chemical composition caffeine, which is significantly different from the drink made from coffee beans. Therefore, a cup of weak tea will not cause excessive excitement, leading to tachycardia and arrhythmia.

Normalization of the digestive system

Stimulation of work digestive tract comes from tannin, a phenolic compound in black tea. The amount of gastric juice increases, thereby the process of digestion of food is accelerated. The bactericidal properties of black tea contribute to the destruction of pathogenic bacteria - the intestinal microflora is restored. Moderate consumption of tea can be a good preventive measure for many diseases of the gastrointestinal tract. The presence of proteins in black tea allows you to quickly satisfy your hunger, which is a huge plus for people who want to lose extra pounds.

Strengthening the skeletal system

Black tea contains many different vitamins and microelements, but its importance for strengthening bones is due to the large amount of fluorine. Thanks to this chemical element, it strengthens musculoskeletal system of a person, teeth are protected from caries and destruction. Japanese scientists have proven the ability of black tea to improve the condition of people with osteoporosis. In this disease, there is a decrease in bone density, and the polyphenol in black tea leads to a decrease in the number of osteoclasts. Over time, the skeletal system is strengthened, and the general condition of the patient improves.

Impact on the immune system

Research projects by scientists have proven the ability of black tea to provide positive influence on immune system. To do this, you need to brew weak tea with the addition of honey and lemon. Essential oils, found in dried leaves, are excellent at fighting pathogens. This strengthens immune defense organism. During colds and viral diseases thermoregulation increases, increasing the excretion of harmful bacteria along with sweat. All this in combination helps a person to quickly cope with the disease and feel a significant improvement. general condition. Hot drink has the ability to increase blood pressure, useful for people with hypotension. The leaves of the tea bush are saturated with Theophylline, an alkaloid that promotes vasodilation and the return of their natural elasticity. Due to this, the blood flow is accelerated throughout cardiovascular system which reduces the chances of blood clots. It is recommended to drink 2-3 cups of black tea for the prevention of atherosclerosis.

The diuretic properties of black tea help to quickly remove accumulated toxins from the body. These harmful compounds are formed in the human body mainly due to the use of substandard products and from a polluted environment. Tea can also be washed out of genitourinary system pathogenic bacteria. At various diseases kidney and Bladder drinking black tea reduces puffiness and stone formation.

Anti-cancer action

For many years, research by scientists has focused on identifying the anti-cancer effect of black tea on the human body. The arguments proving this theory are the ability of tea to purify the blood, bind and remove carcinogens and radioactive substances. Thus, it can be assumed that black tea can be used to prevent anemia, radiation sickness, and skin cancer.

Use in cosmetology

Women use brewed black tea to protect their skin from sunburn, and a beautiful and even tan is provided by tannins. IN cosmetic purposes a kind of tea lotion is used, which needs to be wiped every day on the skin of the face. A healthy complexion is preserved, swelling and bruising under the eyes are removed, and the skin receives the tonic effect it needs. Also, black tea, when used externally, makes the skin supple, and disinfectant properties help relieve inflammation and irritation.

Harm

Regardless of all the beneficial properties of black tea, like any other product, it can harm the body in some cases. People with caffeine intolerance should not drink black tea. They may experience side effects such as dizziness, tachycardia, and hand tremors. There is a risk of developing gout disease due to the breakdown of purines - natural substances found in leaves. The substances themselves are necessary for all cells in the human body, but their decay forms uric acid. It just helps salts accumulate in the joints.

The danger to the human body is frequent use too strong tea. Due to the diuretic action, such tea is able to remove not only harmful substances from the body, but also vital trace elements - magnesium and calcium. Decreased levels of calcium in the body negatively affect the health of teeth and bones, and a lack of magnesium disrupts the functioning of the nervous system. Pregnant women are not recommended to drink tea more than 2 times a day. Although the tea is saturated useful vitamins and trace elements, its excessive use can lead to insufficient weight gain in the gestating fetus.

Contraindications

1. Acute course of diseases of the gastrointestinal tract;
2. Hypertension;
3. Inflammatory period in kidney disease;
4. During toxicosis of pregnant women;
5. Chronic insomnia;
6. With a disease accompanied by high body temperature;
7. Phlebeurysm;
8. Glaucoma.

Black tea in most cases has a beneficial effect on the body. A person with moderate use can rejuvenate to a certain extent and feel vigorous and healthy. Thanks to medicinal properties And excellent taste the popularity of tea does not fall, but admirers wonderful drink are only added.

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And tannins, which in large quantities cause insomnia and headaches. For the average person, caffeine intake should not exceed 300 mg per day. Tannin belongs to the category of anti-nutrients. This means that it interferes with the penetration of certain beneficial substances into the body, such as calcium. That is why it is useful to add some milk to tea so that the calcium contained in it has time to enter the body. On the other hand, milk contains casein, which deprives beneficial antioxidants in the tea of ​​their strength.

One or two cups of strong tea a day won't hurt. But if you are addicted to strong tea, then this amount is no longer enough. And then the harm from it is much more than good.

A lot depends on the quality of the tea. Some manufacturers deliberately neglect the norms and add special impurities to the tea, which color the tea leaves and make it stronger. And such a "strong" tea especially. Recognize the difference between tinted and natural tea you can dip the bag in cold water. If tea colors water, then it harmful dyes.

Very strong tea in large quantities affects the color of the skin, and it turns yellow.

From a large number strong tea is possible. At the same time, there are headache, nausea, dizziness, abdominal pain, surrounding objects are perceived as blurry, coordination of movements is disturbed. The reason for this is that tea regulates blood sugar levels. IN moderate amounts drinking strong tea can prevent diabetes. Too much strong tea causes the body to store and limit sugar, and you begin to miss it.

In this case, you should stop drinking tea and eat or drink something to increase the level of sugar. It can be ice cream, condensed milk, sweet biscuits or bread and butter.

If you are a strong tea lover and like to drink it often, it is better to stick to one type of tea and make sure that the amount of tea leaves brewed does not exceed 20 g per day.

It is better to drink weak tea. It is much more useful than strong in the long run.

Useful properties of strong tea

On the contrary, if you drink strong tea in small portions, then from it is huge. Strong tea gives a charge and energy not worse than coffee. It is due to the fact that high body temperature, eliminates the influence of poisons, nourishes the lungs, cleanses the mucous membranes, stimulates urination, and helps the body digest fats.

In addition, strong tea sobers up a person in a state of alcohol intoxication. Caffeine signals the kidneys, which perform a cleansing function.

The harm of green tea is the last thing apologists want to hear about this really tasty and healthy drink. Green tea can be drunk always and for everyone, millions of people are sure! And yes - green tea is one of the most popular herbal drinks due to its purported health benefits, including weight loss. Although the benefits of green tea have been scientifically proven in one, but not in another. When consumed in moderation, green tea is generally considered safe for adults.

People with a low tolerance for caffeine may experience the harm of green tea even when drinking. a small amount of drink. In addition, people with certain health problems may only worsen their condition by drinking green tea. In this case, it is recommended to limit your daily consumption of green tea to two cups.

This article is about potential harm green tea based on facts Tea Council Great Britain (UK Tea Council): someone, but the British are very kind to tea and send to the study of this drink, probably as much scientific potential as no one else in the world.

When green tea is bad: 19 side effects of green tea

As a rule, the side effects of green tea consumption are associated with caffeine, which, if ingested in large quantities, can lead to aggravation and various health problems.

1. Harm of green tea for stomach problems

Avoid drinking green tea on an empty stomach because it increases the acidity of the stomach, increasing the risk of nausea, stomach pain and constipation due to the tannins it contains.

The best time to drink green tea is between meals or after meals. People with acid reflux or peptic ulcer should not drink green tea in excessive amounts. According to a 1984 study, green tea is a strong stimulant of stomach acid. Scientists have found that adding milk and sugar to tea can reduce these stimulating properties of stomach acid.

It is correct to brew green tea at a temperature between 70 and 90 degrees Celsius, as in some cases the high temperature of green tea brewing can cause side effects. Use too hot water contributes to indigestion or heartburn.

2. How to drink green tea with iron deficiency and anemia

Apparently, green tea reduces the absorption of iron from food, so consuming too much green tea can be hazardous to health. By the way, the lethal dose of caffeine in green tea is considered to be 10 to 14 g (150 to 200 mg/kg).

What's more, green tea reduces the absorption of non-heme iron, which is found in dairy products, eggs, beans, and others. food products plant origin. According to a 2001 study, tea reduces the bioavailability of this type of iron by 25 percent. To prevent this, you need to squeeze a lemon into a cup with green tea or add vegetables or fruits rich in vitamin C to your diet, as this vitamin improves the absorption of non-heme iron. Products with high content vitamin C - lemon, broccoli, dark greens, tomatoes, etc.

According to the UK National Cancer Institute, best time to drink green tea if you are anemic between meals.

3. Green tea and headache

Scientific studies have shown that caffeine increases the risk of chronic daily headaches.

4. Green tea can cause anxiety, nervousness and sleep problems

Caffeine is a stimulant and a derivative of the purine base xanthine. Depending on xanthine sensitivity, which is individual, caffeine can cause anxiety and sleep problems. This purine base blocks sleep hormones in the brain and increases the secretion of adrenaline.

5. Irregular or fast heartbeat

6. Diarrhea

Since caffeine relaxes the muscles in the colon, it promotes peristalsis. Due to this laxative effect, green tea may be contraindicated for some people.

7. Vomiting

Caffeine can even cause nausea because it can affect the movement of food through the esophagus by relaxing the muscles in the esophagus.

8. Heartburn

Due to the ability of caffeine to stimulate the secretion of acid in the stomach, green tea can lead to an unpleasant condition similar to heartburn.

9. Muscle tremor

Caffeine can regulate calcium channels in cells, thus causing muscle tremors.

10. Dizziness

Caffeine can even cause dizziness and motion sickness because it reduces blood flow to the brain.

11. Ringing in the ears

12. Seizures

Excessive amounts of caffeine can stimulate the central nervous system, activating neurons, leading to seizures.

13. The harm of green tea in diabetes

Since caffeine can affect your blood sugar levels, you need to monitor it carefully if you have diabetes and consume green tea on a regular basis.

14. Bleeding

15. The harm of green tea in glaucoma

Intraocular pressure rises within 30 minutes after drinking a cup of green tea; the effect lasts about 90 minutes.

16. The harm of green tea in liver diseases

Medicine knows cases when liver disease is associated with green tea extract. Apparently, the caffeine found in green tea can build up, thereby exacerbating an existing liver problem.

17. High blood pressure and the harm of green tea

Another side effect of caffeine from green tea is the ability to increase blood pressure blood, which is already high. But someone who drinks green tea or some other caffeinated drink on an occasional basis shouldn't have this problem.

18. How to drink green tea for osteoporosis

Green tea can increase the excretion of calcium through the urine, thus contributing to the development of bone problems such as osteoporosis, especially in patients at increased risk for this disease. They should limit their daily caffeine intake to less than 300 milligrams, that's two to three cups of green tea, and take calcium supplements.

19. Harm of green tea during pregnancy. How to drink green tea during pregnancy

Green tea drink contains caffeine, tannic acids and catechins - all three substances are associated with the risk of pregnancy. Pregnant and lactating women are advised to limit their daily intake of green tea to 2 cups per day, which is about 200 milligrams of caffeine. More green tea consumption may increase the risk of miscarriage.

Problems related to nutrient absorption in children

Green tea contains tannins, which can block the absorption of proteins and fats in children. On the other hand, the caffeine content can lead to overstimulation.

Can I drink green tea while taking medication?

Green tea can cause side effects when consumed with the following medications and substances:

Weak connection

Fluconazole, alcohol, antidiabetic, Terbinafine and Mexiletine (Mexitil).

Moderate connection

Quinolone antibiotics, adenosine, contraceptives, Clozapine (Clozaril), Cimetidine (Tagamet), Dipyridamole (Persantine), estrogen tablets, Disulfiram (Antabuse), Fluvoxamine (Luvox), depression medications, lithium medications, Hepatotoxic drugs, Phenobarbita (Nembutal) , Antiplatelets/anticoagulants, Phenylpropanolamine, Theophylline, Riluzole (Rilutek), Warfarin, and Verapamil.

strong connection

Ephedrine, Amphetamines, Cocaine, Nicotine and other stimulants.

How much green tea to drink per day

According to the UK Tea Council, we should not drink more than six cups of green tea a day. In fact, the organization's experts say that 3-4 cups of green tea provides the health benefits of green tea. Drinking up to 5 cups of green tea a day is considered safe. People in Asian countries typically consume 3 cups of green tea per day, which provides them with 240 to 320 mg of polyphenols, the active ingredients in this drink.

The most common way to brew green tea is to add a teaspoon of green tea leaves to a glass of boiled water.
Let the tea cool down a bit before enjoying it. Drinking tea that is too hot is thought to contribute to the development of throat cancer, while scalding tea can lead to damage. digestive system. It is always better to consume freshly brewed tea to get most its medical benefits because the amount of compounds in it, like vitamins C and B, theanine and catechins, decrease over time due to oxidation. If you are re-steeping tea leaves, make sure you do so in moderation, as they can release harmful and even cancerous substances with each successive steaming. Also, antibacterial properties of this tea decrease over time, so old tea may contain harmful bacteria.

Conclusion: when green tea is harmful

If you are taking any of these medications or if you suffer from any of the conditions listed above, be careful when drinking green tea and consult your doctor for the recommended dosage. daily dose green tea. In general, you should not stop drinking green tea, just remember that moderation is always the key to health.

Denial of responsibility: The information provided in this article is about how to brew and drink green tea, is intended for the information of the reader only. It cannot be a substitute for the advice of a health professional.