Side effects of drinking a lot of black tea, there are many kinds of tea in the market at present. Now black tea is gradually becoming familiar to consumers. There are many nutrients in black tea that are beneficial to the human body. Although drinking tea is beneficial to physical and mental health, there must be a degree. Let's take a look at the side effects of drinking a lot of black tea.

Side effects of drinking a lot of black tea 1 1, calcium loss

The fluorine content in black tea is high. Coupled with the water factor, drinking more of this kind of black tea will make calcium ions in the human body synthesize calcium fluoride, which is not easy to absorb and will cause calcium loss in the human body.

2, the teeth turn black

There are many tea pigments in black tea. If you drink black tea often and don't pay attention to brushing your teeth, it will leave tea stains on your teeth, just like tea stains on tea sets.

3, causing anemia

Tannic acid and tannic acid in black tea will combine with iron ions in the body, which will also cause the body to absorb iron ions, thus affecting hematopoietic function. Therefore, people with anemia during menstruation should drink less or not drink black tea.

Taboos for drinking black tea

1, neurasthenia, drink tea carefully

Caffeine in tea has the function of exciting the nerve center. Drinking strong tea for neurasthenia, especially in the afternoon and evening, will cause insomnia and aggravate the condition.

2, pregnant women avoid drinking tea

In particular, it is not suitable to drink strong tea, which contains a lot of tea polyphenols and caffeine, which has many unfavorable factors for the growth of the fetus in the mother's womb. In order to make the fetus's intelligence develop normally and avoid excessive stimulation of caffeine to the fetus, pregnant women should drink less or not drink tea.

3. Avoid drinking tea if you have a fever

Caffeine in tea can not only raise the body temperature, but also reduce the efficacy.

4, liver patients avoid drinking tea.

Most substances such as caffeine in tea are metabolized by the liver. If the liver is sick, drinking too much tea exceeds the metabolic capacity of the liver, it will damage the liver tissue.

5, suffering from severe arteriosclerosis, hypertensive patients can not drink black tea.

Such people should be careful when drinking black tea, at least when their condition is unstable, because black tea contains theophylline, caffeine, theobromine and other active substances, which is a potential danger to people with existing cerebral arteriosclerosis, and it may promote the formation of cerebral thrombosis.

6, anemia patients can not drink black tea.

Tannic acid in black tea leaves can combine with iron to form an insoluble final compound, so that the body can not get enough iron sources, so anemia patients should not drink black tea.

Side effects of drinking a lot of black tea 2 1. Iron deficiency anemia.

I don't know if you have heard of tannic acid. Tannic acid can kill bacteria, diminish inflammation and detoxify. There are many tannic acid components in black tea, but tannic acid can react with iron to produce a black substance that is not easy to decompose-iron tannic acid. It is necessary to know that the body needs a lot of iron, which plays an essential role in our blood regeneration. Once we drink too much black tea, the tannic acid in it will react with iron, causing iron deficiency anemia in the human body.

Second, there are symptoms of calcium deficiency

In addition to tannic acid, there is also an element in black tea-fluoride, which can react with calcium, and also produce a component that is not easily absorbed-calcium fluoride. I believe everyone knows how important calcium is to our human bones. Once the body lacks calcium, not only the bones will become more brittle, but also the teeth will fall off, which will also cause various diseases.

Third, lower blood pressure, blood sugar and blood fat.

In fact, for people with hypertension, hyperglycemia and hyperlipidemia, black tea is definitely a tea that is beneficial to health, because black tea has a good effect of lowering the three highs. But we can't ignore another group, that is, people with low blood sugar and blood pressure, especially those with hypoglycemia, are very common, so for those with hypoglycemia and hypotension, black tea can't be drunk for a long time.

What are the hazards of drinking black tea?

1, damage to the stomach

Drink a lot of black tea, and you will drink a lot of caffeine. Caffeine can refresh your mind, but if you take too much caffeine, it will make the central nervous system too excited, which will lead to the acceleration of gastric peristalsis and the hypersecretion of gastric wall cells. The stimulated stomach will secrete too much gastric acid and the stimulation to the gastric mucosa will be strengthened. Eventually, it will easily cause gastric ulcer. In addition, if you drink too much caffeine, you will become dependent and addicted, thus forming a vicious circle, damaging the stomach and affecting the digestive system.

2, affect the absorption

There is a substance called tannic acid in black tea, which is easy to combine with protein, vitamin B 1 and iron ions in food, so that these nutrients cannot be absorbed normally. If you drink a lot of black tea, it is easy to cause nutrient deficiency and produce corresponding symptoms, such as anemia and constipation, which will do some harm to your body.

Side effects of drinking a lot of black tea 3 Side effects and contraindications of drinking black tea

First, pregnant women and lactating women should not drink black tea

Black tea contains a lot of tea polyphenols, caffeine, etc., which has many unfavorable factors for the intellectual development of the fetus, so pregnant women should drink less tea or not, especially strong tea.

Breast-feeding women should not drink strong black tea, too much caffeine will enter the milk, and the baby regrets drinking milk containing too much caffeine, which may lead to less sleep and more crying.

Second, people with these diseases should not drink black tea.

1 People suffering from malnutrition or protein's deficiency should not drink black tea;

Black tea can help digestion and relieve boredom, so many people drink black tea to lose weight. But for people who are too thin, suffering from malnutrition or protein's deficiency, black tea will hinder the absorption of protein, which is very unfavorable to them.

2, people with anemia should not drink black tea:

Tannic acid in black tea leaves can combine with iron to form insoluble substances, so that the human body can not get enough iron, so anemia patients are not suitable for drinking black tea.

3, people with hypoglycemia should not drink black tea:

Black tea has the effect of lowering blood sugar. Black tea leaves can quickly lower blood sugar in a short time, so it is not suitable for patients with fasting and hypoglycemia to drink black tea.

4. People with neurasthenia should not drink black tea:

People with neurasthenia are often prone to insomnia and dreaminess. Caffeine and aromatic substances in black tea are stimulants, which can excite the central nervous system and brain, accelerate the heartbeat and blood flow, and thus aggravate insomnia. Therefore, people with neurasthenia had better not drink black tea, especially before going to bed.

5, people with fever should not drink black tea:

Caffeine in tea will raise the body temperature and reduce the efficacy. Drinking tea with a fever is like adding fuel to the fire, so people with a fever are not suitable for drinking tea.

6, liver patients should not drink black tea:

Most of caffeine and other substances contained in tea are metabolized by the liver, so if the liver has diseases, drinking too much tea will exceed the metabolic capacity of the liver and damage the liver tissue.

7, patients with gastric ulcer should not drink black tea:

Caffeine in tea can promote the secretion of gastric acid, increase the concentration of gastric acid, induce ulcers and even gastric perforation.

Third, it is not suitable to drink black tea during menstruation.

It is not suitable to drink tea during menstruation, especially strong tea, because drinking tea during menstruation may aggravate menstrual syndrome.

4. Vegetarians should not drink black tea.

Black tea will hinder the body's absorption of some vitamins. People who eat vegetarian tea all the year round can easily absorb nutrients such as vitamin B, calcium and iron, so vegetarians had better not drink black tea.