If you're hungry, don't even drink coffee when your blood pressure is high.

Aroused by coffee in the morning, a cup of refreshing in the afternoon, perhaps a cup of digestion after dinner... Nowadays, coffee is more and more accepted and loved by people. Coffee also has a number of "legends", drinking coffee can lose weight, drinking coffee helps vision, drinking coffee can prevent stroke, but also anti-cancer... However, we have to remind that the caffeine in coffee affects the body's mechanism is very complex, both on hormone levels regulation, but also on the impact of specific gene expression activity. Therefore, some people, or some times, are not suitable for drinking coffee. Furthermore, coffee should not be excessive, no matter how good it is. People who drink 5 cups of coffee a day are defined as heavy coffee drinkers in the study. If they drink too much, they may have the same effect as taking medicine!

Expert interviewed: Professor Liu Xinfeng, Department of Neurology, Nanjing General Hospital, Nanjing Military Region

This edition was written by Li Lanling

1. Drinking coffee after a full meal makes your esophagus narrow

Case: There is a guy is an IT man, often stay up late overtime, over the years, he developed a habit, after dinner to have a cup of coffee, refreshing!

A while ago, he inexplicably lost weight (from more than 150 pounds to more than 130 pounds). And swallowing things more and more difficult, drink cold boiled water have to swallow, otherwise they will all vomit out. Multiple gastroscopy and imaging examinations were highly suspected of esophageal cancer. Finally, he went to the provincial hospital, ready to undergo surgery after diagnosis. But the plot reversed, gastroenterology doctors through endoscopic diagnosis and treatment, found that he did not have cancer, is benign esophageal stenosis. Normal esophageal diameter is generally 2-2.5 cm, his esophagus was only about 0.3 cm.

Doctors said his benign esophageal stricture was caused by reflux esophagitis, and his habit of drinking coffee after satiety every day was the cause of the disease.

What does coffee have to do with reflux?

Caffeine in coffee stimulates the sphincter muscle at the lower end of the esophagus, which is originally closed, so that it relaxes and allows the contents of the stomach and duodenum to flow back to the esophagus. In this way, gastric acid, pepsin, bile salts and pancreatin damage the esophageal mucosa, causing inflammation, erosion and ulcer.

The IT man's habit of drinking coffee after satiety lasted for a long time, and the esophagus repeatedly eroded, ulcerated, formed granulation, scar, and finally contracted to cause esophageal stricture.

Coffee on an empty stomach hurts your stomach.

Case: "Enjoy a cup of good coffee in the morning light, as if all the cells in your body have been awakened." Wenwen, 23, who works for an advertising agency, drinks coffee as a ritual. But recently she discovered that after a cup of coffee, the spirit is refreshed, but the stomach will ache for a long time.

What's wrong with coffee on an empty stomach?

Drinking coffee on an empty stomach stimulates and excites sympathetic nerves, which reduces appetite.

Furthermore, caffeine is a strong stimulant of gastric acid secretion. On an empty stomach, strong acid stimulates gastric mucosa, causing discomfort. Gastric ulcer or duodenum, will aggravate the disease.

Experts at the American University of Health Sciences say drinking coffee immediately after waking up can make people sensitive. It is recommended to eat bread and other staple foods before drinking coffee. Don't drink it if you have stomach problems.

People with high blood pressure drink coffee carefully when they are stressed

Case 3: A department manager drinks a cup of coffee every morning after getting up; after working for a few hours, he feels that his spirit is getting worse or when he is under great pressure at work, he will drink coffee again to refresh himself and relieve his pressure; when he is in a bad mood, he also drinks a cup of coffee to change his mood.

How to drink coffee when you are nervous and stressed?

The study found that even the dose of caffeine in a cup of coffee (140 mg) can affect blood pressure, especially under stress. If you add emotional tension to this, it will have a dangerous multiplier effect.

People who consume too much caffeine, especially those with heart disease, are prone to arrhythmia and cardiovascular disease.

A team of researchers from La Trobe University in Melbourne, Australia, found that people who are stressed and coffee drinkers are three times more likely to have auditory hallucinations and hallucinations. The effect is similar to taking too many caffeinated drugs.

Coffee's refreshing effect varies from person to person

Case 4: A mother said that her daughter was nervous in high school, slept less at night, dozed off in class, couldn't listen to class, told me to refresh herself with coffee, and said that her classmates were drinking.

People think of coffee first.

Scientists dispute the role of caffeine.

An experiment conducted by the Sleep Medicine Research Center at St. Luke's Hospital in the United States found that caffeine is refreshing, but the effect of this refreshing varies from person to person.

An article in the Journal of Neuropsychopharmacology says that drinking coffee doesn't make you more alert, focused, or responsive, it just keeps you awake: "I drank coffee and drove across Europe, and I knew it would keep me awake. But if I'm writing a science paper late at night, coffee doesn't keep me focused or sharp."

Why does it stay awake?

The reason is that caffeine blocks the action of a chemical in the brain called adenosine. Normally adenosine slows the body down, but caffeine keeps the chemical from reaching cells, so you stay high. But the caffeine effect wears off quickly!

Drinking a lot of coffee consumes vitamin B groups in the body

After the caffeine effect has passed, people will feel tired due to the continuous impact of large amounts of adenosine. When many friends work overtime, in order to keep themselves awake, they will continue to drink strong coffee, so what will happen?

Drinking a lot of coffee will cause the metabolic rate to accelerate, consuming vitamin B groups related to nerve and muscle coordination in the body, among which vitamin B1 can maintain the balance and stability of the nervous system.

People who lack vitamin B groups are more likely to be tired, so they will drink more coffee, need more and more, but the effect is getting worse and worse, forming a vicious circle and developing the habit of drinking coffee.

Therefore, when you must stay up late, add more vitamin B groups, but more effective.

6 "Excessive coffee drinking" is a manifestation of drug dependence

Case: A sales executive of a foreign-funded enterprise, she studied high school pressure, often drink coffee to refresh herself. After work, work pressure, insomnia at night, no spirit during the day, she will coffee as a refreshing "panacea." She gets up early for a cup of coffee. At work, drink at least eight glasses, extra strong, and one before bed at night. The "tradition" of drinking ten glasses a day has been around for at least a year. One night, I forgot to drink coffee and couldn't sleep.

Too much coffee, too much trouble. She says her brain doesn't seem to work without coffee. "I forgot to bring coffee with me when I was on a business trip. Once I don't drink it, I feel uncomfortable and I feel like I have a cold."

An article published in the Journal of Neuropsychopharmacology suggests that drinking coffee all the time is actually a sign of drug addiction.

"People who consume caffeine regularly end up dependent on it, and if you keep them away from caffeine, their performance will be lower than normal."

Studies have shown that constant caffeine intake causes a decrease in the brain's production of the mood-enhancing hormone noradrenaline, leaving the body to pursue that filling and empty substance caffeine.

Caffeine affects men more strongly

Case in point: We have coworkers who can drink six cups of coffee a day without worry, and friends who have a cappuccino after dinner and sleep like babies within an hour.

Case study: a senior high school student always studied late at night, so the first thing she got up was to make coffee. After drinking it, she felt refreshed, but her acne was very severe. But for the college entrance exam, she still regards morning sparkling coffee as her first homework.

Why does coffee work so differently for everyone?

The study found that the body's chemical processes for processing caffeine vary based on several key factors-

Brain sensitivity to caffeine is related to the amount of caffeine binding to adrenergic receptors. Those who can bind more effectively to adrenergic receptors tend to be more sensitive to coffee.

An enzyme in the liver helps the body metabolize caffeine. Those who produced fewer metabolic enzymes took longer to clear caffeine, had longer caffeine effects, and had more long-lasting side effects.

There are also gender differences in the body's ability to process caffeine, with women naturally metabolizing faster than men. Therefore, caffeine affects men more strongly.