1, easy to affect the heart. Caffeine acts on the heart in two ways: caffeine affects the brain center that regulates the cardiovascular system, and it also acts on the human heart. Excessive caffeine will increase the heart rate of people who are intolerant of caffeine by 10 to 20 times per minute, and may cause transient arrhythmia.

2, easy to affect people's digestive system. Acidity, oiliness and caffeine in coffee can stimulate gastric mucosa and promote gastric acid secretion. People with stomach problems, drinking a lot of caffeinated drinks for a long time, will lead to the aggravation of stomach problems.

3, easy to affect the kidneys. People usually go to the toilet after drinking coffee, because caffeine can affect adenosine receptors in human kidneys and play a role similar to diuretics. Therefore, caffeine may also slow down the release of an antidiuretic hormone from the brain, which will reduce the production of urine.

Extended data:

Usually, when people who drink a lot of coffee stop drinking coffee, they will have symptoms such as headache, irritability, muscle tension and nervousness. Only after taking caffeine will the symptoms disappear, similar to caffeine addiction.

During pregnancy and breastfeeding, women should drink coffee in moderation. If they consume too much coffee, caffeine will penetrate into the placenta and appear in breast milk.

Drinking a lot of coffee at night can lead to a very high spirit. Caffeine can affect people's sleep within 4 hours after drinking coffee.

References:

People's Network-Coffee affects six parts of the body. 7 taboos for drinking coffee carefully.

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