The smell of coffee alone triggers a real desire for the new day, especially at breakfast, which shows that coffee also has an invigorating effect on the mental, psychological side. But there are also those who do not get tired of seeing coffee as a potential health hazard, which only gives people inner restlessness, sleep disorders and nervousness. Which of these is true, and to what extent, will be briefly reported here:
What are the limits of coffee enjoyment?
Hans Hauner should know, he is director at the EKFZ ("Else Kröner-Fresenius-Center for Nutritional Medicine" at the Technical University of Munich) and says that coffee can only be dangerous for our body because of its caffeine content if it is constantly drunk in excess.
Nutrition expert Gabriele Graf, who is a member of the NRW consumer advice center in Düsseldorf, adds that up to 400 mg of caffeine are harmless for an adult if their intake is distributed throughout the day. Converted that means that an adult humans can take daily problem-free 4 to 5 cups Espresso or up to 8 cups black tea to itself. Completely differently it behaves however with pregnant or nursing women, continues Mrs. count. Caffeine passes through the placenta virtually unfiltered and thus enters directly into the bloodstream of the unborn child, whose small liver is not yet able to break down caffeine quickly enough. Therefore, according to the nutrition expert's advice, pregnant women or nursing mothers should only give in to their desire for coffee to a very limited extent.
As a guide, 200 ml of filter coffee, which is a large cup, contains about 90 mg of caffeine.
How quickly does the caffeine in coffee take effect?
Margret Morlo from the "Association for Nutrition and Dietetics" answers this question to the effect that the stimulating effect of caffeine normally only sets in 15 - 30 minutes after drinking coffee. It takes that long for the caffeine to be distributed throughout the body to the brain via the bloodstream. The complete breakdown of caffeine by the liver, spleen and kidneys then takes several hours. In this case, too, we speak of a half-life, which in healthy adults averages about 4 hours.
To explain the term half-life: In this case, this refers to the period of time (t2 - t1) that must elapse until the caffeine content in the blood at time t1 has dropped to exactly half the caffeine content at time t2.
At what time of day should coffee no longer be drunk?
There is an increased likelihood that for certain people, coffee later in the evening makes it more difficult to fall asleep. However, there are also many people who report just the opposite and consciously drink another coffee before going to bed. A rule can not really be derived, the reaction to (late) caffeine is individually very different.
Are there any other side effects of caffeine?
In almost all people, caffeine has the effect of increasing the heart rate, which can be counted from the pulse, and also the blood pressure. However, this does not simultaneously mean an increase in the risk of heart attack or an acceleration of arteriosclerosis. In this respect, even hypertensive patients can drink coffee in moderation. In the case of cardiac arrhythmia, however, caution is advised. In this case, the attending physician should be consulted. Generally can be stated: People who drink gallons of strong coffee usually have gastrointestinal problems (gastritis), and a certain hyperactivity can develop, which can even lead to anxiety.
Do withdrawal symptoms occur after stopping daily coffee ration?
The body does get used to the daily dose of caffeine. In the expectation that caffeine will be absorbed, the body automatically screws the heart rate, pulse and blood pressure down a bit. If the balancing portion of caffeine is then missing, these body values sink a little too far, and headaches and concentration difficulties can occur. Nevertheless, it does not make sense to immediately classify caffeine as an addictive substance.
Does coffee also have a health-promoting effect?
Caffeine is an antagonist of adenosine, a messenger substance produced by the body to make us tired. Therefore, caffeine makes us more alert and also improves our
Ability to concentrate. Since coffee also contains chlorogenic acid, the effect of insulin is somewhat intensified, which can have a positive effect on diabetes patients. There are even studies that have come to the conclusion that coffee drinkers grow slightly older and have a lower risk of colon cancer. It would be interesting to find out the principals here.
Last but not least: It is often said that coffee does not count as a liquid in view of our daily liquid requirement of 2 to 3 liters. But this is not correct. If the coffee is not extremely strong, it may very well be included in our fluid balance.
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