It is good to drink less green tea (light tea), especially if you drink too much strong tea, it is easy to cause autonomic nervous disorder, and so is coffee, causing dizziness, insomnia, palpitation and other symptoms! Drinking tea is different from drinking tea in four seasons. Drinking tea in four seasons is different, namely, drinking scented tea in spring, drinking green tea in summer, drinking green tea in autumn and drinking black tea in winter. The reason is that people who drink scented tea in spring can emit the cold evil accumulated in the human body all winter, and the rich fragrance can promote the occurrence of human yang. In summer, drinking green tea is better. Green tea tastes bitter and cold, which can clear away heat and relieve summer heat, detoxify and quench thirst, and strengthen the heart. In autumn, drinking green tea is better. This kind of tea is neither too hot nor too cold, which can eliminate residual heat in the body and restore body fluid. Drinking black tea in winter is ideal. Black tea is sweet and warm, rich in protein, which can help digestion, tonify the body and strengthen the body. Drink 2 ~ 6 grams of tea every day. Although tea contains a variety of vitamins and amino acids, drinking tea has a certain effect on clearing oil, relieving boredom, enhancing nerve excitement and promoting digestion and diuresis, but not the more you drink, the better, and not everyone is suitable for drinking tea. Generally speaking, 65438+ 0-2 times a day, 2-3 grams each time, is more appropriate. It is not suitable for patients with neurasthenia, insomnia, hyperthyroidism, tuberculosis, heart disease, gastropathy and intestinal ulcer, nor for lactation period, pregnant women and infants. Not drinking strong tea will make the body's "excitability" too high, which will adversely affect the cardiovascular system and nervous system. Patients with cardiovascular diseases may have tachycardia or even arrhythmia after drinking strong tea, which leads to repeated illness. It is more important for morning tea drinkers not to drink tea before going to bed. After drinking tea before going to bed, it becomes very difficult for many people to fall asleep, which even seriously affects their mental state the next day. People with neurasthenia or insomnia should pay special attention. Drinking a lot of tea before or during meals is not a big problem, but if you drink a lot of tea or drink too much tea, it will affect the absorption of many macro elements (such as calcium) and trace elements (such as iron and zinc). Pay special attention not to drink tea at the same time when drinking milk or other dairy products. Theophylline and tannic acid in tea will combine with calcium in dairy products to form water-insoluble calcium salts, which will be excreted, greatly reducing the nutritional value of dairy products. Drinking too much tea is not conducive to digesting a large amount of tannic acid contained in tea. Once it is synthesized with protein, a food in meat, eggs and seafood, it will slow down intestinal peristalsis, which will not only easily cause constipation, but also increase the possibility of toxic or carcinogenic substances being absorbed by the human body. Green tea and medlar can't be drunk together. Both green tea and medlar can be brewed with boiling water, which is very beneficial to the human body. Many people simply put them together to brew. However, a large amount of tannic acid contained in green tea has convergence and adsorption effects, which will adsorb trace elements in Lycium barbarum and produce substances that are difficult for human body to absorb. Therefore, experts suggest: drink green tea in the morning to stimulate appetite and refresh your mind; Drinking Lycium barbarum in the afternoon can enhance physical fitness and have a good sleep. After drinking tea, the alcohol in the wine enters the blood through the gastrointestinal tract, and is converted into acetaldehyde in the liver, which is then converted into acetic acid, which is then decomposed into carbon dioxide and water to be excreted. After drinking tea, theophylline in tea can quickly diuretic the kidney, thus promoting the undecomposed acetaldehyde to enter the kidney prematurely. Acetaldehyde has a great stimulating effect on the kidney, so it will affect the renal function. People who often drink strong tea after drinking are prone to kidney disease. Not only that, the ethanol in wine is very irritating to the cardiovascular system, and tea also has the effect of exciting the heart. The combination of the two enhances the stimulation to the heart, so drinking tea for heart patients is more harmful. The fresher the tea, the better. From a nutritional point of view, the freshest tea is not necessarily the best in nutrients, because the so-called new tea refers to tea that has been picked for less than one month. Because these tea leaves have not been placed for a period of time, some substances that have adverse effects on the body, such as polyphenols, alcohols and aldehydes, have not been completely oxidized. If you drink new tea for a long time, you may have discomfort such as diarrhea and bloating. Too fresh tea is even worse for patients, such as some people with gastric acid deficiency or elderly patients with chronic gastric ulcer, which is even more unsuitable for drinking new tea. New tea will stimulate their gastric mucosa, cause gastrointestinal discomfort and even aggravate their condition. When is constipation not suitable for drinking tea? Because tea polyphenols have a certain astringent effect on gastrointestinal mucosa, it affects the digestion and absorption function of food and causes constipation or aggravation. Caffeine in tea has obvious exciting effect on human central nervous system when neurasthenia or insomnia occurs. Drinking tea, especially strong tea, will make people's brains in an overexcited state and get no rest. Drinking a lot of tea before and after meals will dilute gastric juice and affect digestion when suffering from gastric ulcer. Drinking a lot of tea will greatly increase the secretion of gastric acid, affect the healing of ulcer surface and aggravate the condition. Patients with ulcers should drink less tea, especially not a lot of strong tea. Excessive drinking tea when suffering from heart disease or hypertension will increase the burden on the heart, accelerate the heart rate and raise blood pressure, which is extremely unfavorable to patients with heart disease and hypertension. When suffering from atherosclerosis, tea contains a variety of bioactive substances, such as caffeine, theophylline and theobromine, which can accelerate the excitement of cerebral cortex, cause cerebral vasoconstriction, insufficient blood supply and slow blood flow, and promote cerebral thrombosis. It can also cause coronary artery contraction spasm, myocardial ischemia, angina pectoris, palpitation, chest tightness and arrhythmia. Women's menstrual blood will take away some iron, so women should supplement iron-rich foods at this time, such as spinach, apples, grapes and so on. However, because tea contains as much as 30% to 50% tannic acid, it will hinder the absorption and utilization of iron by intestinal mucosa, and it is easy to precipitate with iron in chyme or iron stone in blood-enriching drugs in the intestine. Women who drink too much strong tea before labor will lose sleep because of the exciting effect of caffeine. If you don't get enough sleep before delivery, you will often be exhausted, painful and weak, and even cause dystocia. Menopause enters menopause, in addition to dizziness and fatigue, sometimes tachycardia, emotional impulse, lack of sleep, and women will also have symptoms such as menstrual disorders. For example, excessive drinking tea will aggravate these symptoms, which is not conducive to a comfortable menopause. Tannic acid in tea during anemia can precipitate iron in diet, which is not easy to absorb. Iron is an important raw material for making red blood cells. Iron deficiency in the body will hinder the production of red blood cells and cause iron deficiency anemia. Long-term tea drinkers often have different degrees of iron deficiency, which has the greatest impact on the constitution of blood deficiency and blood deficiency. Calcium deficiency or fracture will inhibit the absorption of calcium in duodenum because of alkaloids in tea. At the same time, it can also promote the excretion of calcium in urine, so that the calcium in the human body is less and less, leading to calcium deficiency and osteoporosis, making it difficult to recover the fracture. When suffering from gout, because tannic acid in tea will aggravate the patient's condition, it is not suitable for drinking tea, let alone soaking tea for too long. When suffering from osteoporosis, the latest research found that drinking strong tea is one of the important causes of osteoporosis. Drinking strong tea often will lead to calcium deficiency, because on the one hand, caffeine in strong tea will promote the excretion of calcium in urine; On the other hand, caffeine can inhibit the absorption of calcium in the intestine, making the absorption of calcium incomplete. In case of high fever, it is better to give patients with fever boiled water, mineral water or light tea, but it is not advisable to drink strong tea. Theophylline can raise body temperature and aggravate fever, and its diuretic effect will also reduce the efficacy of antipyretic drugs. When taking some drugs, tannic acid in tea often precipitates the effective components of digitalis, iron and Chinese patent medicine supplements, which are not easily absorbed; Taking pepsin or multi-enzyme tablets while drinking tea will coagulate protein in medicine, and the curative effect is difficult to achieve. The concentration of caffeine in strong tea during pregnancy is as high as 10%, which will aggravate the urination and heartbeat of pregnant women, increase the burden on their hearts and kidneys, and induce pregnancy poisoning, which is not conducive to the health of the mother and fetus. If women drink a lot of tea during lactation, the high concentration of tannic acid in tea will be absorbed by mucous membrane and enter the blood circulation, which will converge and inhibit breast secretion, resulting in insufficient milk secretion. On the other hand, caffeine in tea will also enter the baby's body through milk, which will affect the baby's health.