What are the advantages and disadvantages of caffeine in tea?

Caffeine is the most important alkaloid in tea. Its content generally accounts for 2%-4% of the weight of dry tea and accounts for more than 95% of the alkaloids in tea. It is also one of the components of the quality characteristics of tea, and is also related to many health functions of tea, such as cardiotonic, diuretic, and central nervous system stimulation.

Caffeine, which seems ordinary to us now, has actually gone through a tortuous process in the research community. Once upon a time, the most terrifying statement was that caffeine has mutagenic and cumulative toxicity effects.

Someone injected a large dose of pure caffeine into the stomachs of pregnant rats or young rats at one time, causing malformations in the offspring and retarded bone development in the young rats. In 1980, the U.S. Food and Drug Administration (FDA) urged pregnant women to stop eating anything containing caffeine. of food.

This test method is obviously one-sided. Later, some people used experiments to make pregnant rats eat caffeine "little by little", which is more in line with the actual situation of the beverage. The results show that drinking tea by pregnant rats will only improve their health, and there is no need to worry about physiological defects in their offspring. For this reason, the FDA announced in 1984 that it would re-evaluate the 1980 warning.

These experiments also tell us that whether a substance can cause mutations must take into account factors such as the dose, the difference in effects between pure food and mixed systems, and the differences in body metabolism between humans and experimental animals.

In fact, there is no evidence that consuming caffeine causes chromosomal defects that lead to mutations.

We all know that caffeine present in tea soup or tea extract is safe for human health due to its low concentration and the mutual restriction of caffeine with other components in tea. Not only is it safe, the caffeine in tea also has functions such as refreshing, anti-fatigue, diuresis, and detoxification.

However, if you drink tea unreasonably, caffeine may also have side effects that are harmful to your health! Therefore, as far as caffeine is concerned, we should pay attention to the following situations when drinking tea:

1. Do not drink tea before going to bed, especially strong tea, to avoid insomnia. Here, caffeine’s central nervous system stimulation and diuretic effects become harmful to health!

2. Patients with certain diseases, such as severe heart disease and neurasthenia, should also avoid drinking strong tea or drinking too much tea. Especially don't drink tea at night to avoid increasing the load on your heart. Because caffeine can induce gastric acid secretion, patients with gastric ulcers are generally not advised to drink tea.

3. Do not drink tea while taking certain medications. The caffeine in the tea may react with them, causing adverse consequences. For ordinary people, there are still different views on the long-term health effects of long-term drinking of tea with high caffeine content. However, it is generally believed that the caffeine in tea is beneficial to the human body by controlling a certain amount of tea (5-15 grams of dry tea per day) and concentration (not drinking strong tea), and paying attention to the above precautions.
A world-renowned coffee expert once said: "Except for pregnant women, wet nurses and some special patients (such as those with arrhythmia), caffeine is innocent for everyone else." This conclusion can be used as a guideline for our tea drinking.

The general distribution pattern of caffeine in tea leaves has some unique features. Regarding the degree of tenderness of tea trees, it is consistent with the distribution pattern of tea amino acids; in different varieties and seasons, it seems to be consistent with tea polyphenols.

1. The more delicate it is, the more caffeine it has. The younger and more tender parts of the tea tree contain more caffeine, whereas the older the raw materials, the less caffeine they contain.

2. Large leaf species have more caffeine than medium and small leaf species. Large-leaf species generally contain more caffeine than medium- and small-leaf species. This is a conclusion drawn from the caffeine biosynthesis pathway.

3. Summer tea has the highest caffeine content. Summer temperatures are higher, tea trees grow most vigorously, and summer tea contains the highest caffeine. The same goes for tea polyphenols, so summer tea is often bitter and astringent.

4. Tea roasted at high temperature has less caffeine. Caffeine begins to turn into gas and sublimate when the temperature reaches 178°C. Therefore, tea leaves that have been fried at high temperatures for a long time or have a pot-shaking process have relatively less caffeine, and the caffeine part of the tea leaves is reduced during the roasting process.