Relying on coffee to refresh is actually "consuming" energy ahead of time

2023-10-22

Coffee is native to north-central Africa and is a rubiaceae coffee plant that has been drunk by humans for more than 3,000 years. It is one of the most widely circulated beverages in the world, and about 80% of Europeans and Americans have the habit of drinking coffee every day. People love the refreshing effect of coffee, and the wisps of rich aroma are intoxicating.

The refreshing effect of coffee comes from the alkaloids in coffee beans, the most representative of which is caffeine. From a biological evolutionary point of view, caffeine was originally a bitter taste and a certain toxic chemical in plant fruits, used to protect plants from animal eating. Many animals are poisoned by coffee ingestion, however, primates have a strong detoxification ability of their livers due to long-term eating of plant fruits.

Caffeine does not produce extra energy, but rather advances energy

The chemical structure of caffeine is much like adenosine in the human body, which is a product of energy metabolism. Adenosine is continuously produced from the cell and secreted outside the cell, and when it binds to the adenosine receptor on the cell membrane, it is equivalent to telling the cell: "The energy consumption is almost the same, I am tired and need to rest."

In the awake state, adenosine on nerve cells increases every hour, and when it reaches a certain amount, it will produce drowsiness. However, if coffee is drunk at this time, caffeine will bind to adenosine receptors, preempting the binding site of adenosine. But caffeine is not adenosine after all, and it does not trigger intracellular signaling after binding to adenosine receptors, so it does not cause drowsiness. At this time, adenosine is still continuously produced in human cells, and since it cannot bind to receptors on the cell membrane, it wanders between cells. After about four or five hours, caffeine is metabolized by the body, and the accumulated adenosine will occupy almost all adenosine receptors, and the person will feel more sleepy. In this sense, caffeine advances a person's energy, rather than generating additional energy.

Long-term drinking will cause reverse regulation

After drinking coffee for a long time, adenosine receptors will be reverse-regulated, and the expression level on nerve cells will increase. The human body gradually tolerates caffeine, from the initial spirit to the habit after there is no obvious excitement. People who are accustomed to drinking coffee will have a decline in mental state and cognitive ability in the state of abstinence from coffee, and need to consume the same dose of coffee as usual to return to normal levels. In this way, drinking coffee to improve study or productivity is not worth the loss, because you must drink a certain amount every day to maintain normal energy, otherwise it is not as good as normal.

Presumably, some coffee fans saw this conclusion and began to consider quitting coffee. Then after quitting coffee for a period of time, the expression level of adenosine receptors in the human brain will return to normal and return to the state before coffee addiction. Coffee is indeed an addictive substance, but it has no obvious physical and mental harm and withdrawal symptoms compared to drugs, so it can become a legally available commodity.

In addition to caffeine, coffee also contains hundreds of chemicals such as sugars, organic acids, esters, sterols, diterpenes, etc., and the regulation of human functions is also multifaceted. The pros and cons of coffee on health have been controversial, and scientists have counted research reports on the relationship between coffee and health since the 70s of the 20th century, and concluded that under the premise of moderate amounts, the benefits of coffee to the human body are slightly higher than the harms, which can reduce the incidence of senile dementia and some cancers, and the harm is that it is easy to cause women to be less fertile, resulting in osteoporosis.

It is recommended not to exceed two cups per day

Should I drink coffee? The answer varies from person to person. If it is coffee's unique taste and aromatic smell that appeals to you, your love for coffee is deep in your bones, and you don't have to refuse its temptation. If you want to refresh yourself with coffee, you might as well drink it occasionally at important moments to help you perform at an extraordinary level, as is said to be what some athletes do. Coffee is not a doping agent, and the caffeine limit set in a urine test at a sporting event is 12 micrograms per milliliter.

The effects of coffee on the human body are closely related to dosage, and the European Food Safety Authority recommends no more than 400 mg of caffeine per day, which is about two cups of coffee. It is worth noting that for children and adolescents, due to immature brain development, caffeine intake is more stimulating to the nervous system, therefore, experts in the field of educational neuroscience are against drinking by minors. The medical community believes that insomnia, hyperthyroidism, digestive diseases, cardiovascular diseases, and pregnant women should drink less or no coffee.

Finally, I remind everyone that coffee is not the only source of caffeine, tea, cocoa, Coca-Cola, chocolate also have caffeine, if you like these foods should also limit the total intake.