Distorting the brain's rest signals leads to a buildup of fatigue... consuming it with sugar can even trigger feelings of depression.

 "Chemistry" is a distant and difficult word. However, chemistry is working small and large magic in every moment of our daily lives. Professor Lee Kwang-ryeol shares how to solve everyday problems with simple chemistry common sense, along with chemistry stories entwined with safety and industry.

Coffee beans, the raw material of coffee, contain a large amount of caffeine. News 1 The "coffee houses" that appeared in 17th-century Britain were spaces where people shared trade and commerce information. They were also venues where in-depth discussions on science unfolded. In the process, the foundation for modern commerce was laid, and there was explosive scientific development.

While alcohol clouded people's minds, coffee became the foundation of modern intellect. Caffeine, found in coffee and energy drinks, has an outstanding alerting effect. Consuming even a small amount snaps your mind awake. Therefore, it is a ray of light for students with a lot of study material, or writers and reporters chased by deadlines. However, they share something else besides being busy.

The points under their eyes are dark, they have no strength in their bodies, and they suffer from chronic fatigue. This is because caffeine drinks may temporarily supply energy, but ultimately they are "devil drinks" that suck the vitality out of the body. What on earth does caffeine do in the body to give both an alerting effect and exhaustion?

Vitamin C, Taken with Coffee, Becomes Useless When we are active, our brains are also very busy. The brain's main fuel is glucose. The brain consumes glucose and constantly produces a substance called adenosine as waste. Brain cells have adenosine receptors, and adenosine, a byproduct of brain activity, fills these receptors. When the adenosine receptors become saturated, drowsiness rolls in. It is our body's way of letting us know that we "need to rest."

However, caffeine looks very similar to adenosine. As soon as it enters the body, it goes straight to the brain and blocks the adenosine receptor sites. Because adenosine and adenosine receptors cannot bind, the brain tricks itself into thinking there is a lack of adenosine, and we enter a state of alertness. In a state of alertness, people can study and work. In the process, even more adenosine accumulates.

The problem is that caffeine does not stay in the body forever and leaves after a certain amount of time. When the caffeine disappears, the accumulated adenosines that had been chased away from their seats rush toward the adenosine receptors. Naturally, sleepiness pours down. Energy drinks also contain a lot of sugar. When blood sugar spikes in a short time and then plummets, depression can strike along with fatigue. A vicious cycle of seeking sugar once again can occur.

Quite a few people toss back vitamin C or nutritional supplements together with coffee, thinking they are taking care of their health. Since it's annoying to drink water, the thought is to take them while drinking coffee, but this is not a very wise behavior. Vitamin C is a water-soluble vitamin. What remains after being absorbed into the body is excreted with urine. However, caffeine has a powerful diuretic effect. It does not give vitamin C time to be absorbed. Moreover, chemically speaking, vitamin C (ascorbic acid) is acidic, and coffee is also acidic. Pouring two acidic substances all at once into an empty or sensitive stomach can erode the stomach lining and cause heartburn.

Citizens participating in the "2026 Hangang Sleeping Contest". News 1 Drink coffee and sober up? It only adds to the hangover For people who cannot drink well, energy drinks are sometimes recommended as a "secret to becoming stronger at a drinking gathering." The logic is that caffeine's alerting effect suppresses alcohol's sedative effect. Indeed, if you secretly step out in the middle of a drinking gathering and drink a beverage packed with caffeine, you seem to snap awake.

Has the brain really returned to a normal state thanks to caffeine? Not at all. The brain is already operating slowly due to alcohol's action. At this time, caffeine merely tricks a person into thinking "I'm sober." In the end, people may drink alcohol close to a lethal dose without knowing they are drunk, or foolishly grab the steering wheel. The fact that both alcohol and caffeine are "dehydration culprits" that rob the body of moisture is also a problem. If the two cooperate and drain all the moisture in the blood vessels, you can experience the worst hangover and kidney damage the next day.

When chatting and leisurely enjoying fragrant coffee, an appropriate amount of caffeine makes you forget the brain's fatigue signals for a moment and brings vitality to life. However, caffeine can never be a fundamental method to resolve fatigue. To protect health, let's take nutritional supplements with plain water. At drinking gatherings, let's refrain from caffeine intake.

From late afternoon onward, let's keep caffeine away so we can fall asleep on time. Only then does the body recover and not age. Let's not forget: arousal through caffeine is nothing more than temporarily postponing fatigue. Professor Lee Kwang-ryeol… received a bachelor's degree in chemistry from KAIST and a doctorate in chemistry from the University of Illinois, and has been serving as a professor in the Department of Chemistry at Korea University since 2003. His representative books include "Suspicious Chemistry Book for the Lazy", "Elementary All-Star Science", and "Puberty is My First Time".

[ⓒ Global Economic Times. 무단전재-재배포 금지]