How Healthy is Coffee?

Coffee makes you fit and awake. He used to have a pretty bad image. It has now been shown that coffee can even be good for your health.

What is caffeine?

More than 1000 components of coffee have now been identified. Caffeine is not only the best known, but also the most effective. Chemically, caffeine is one of the alkaloids – and is pharmacologically and medically classified as a drug. It has a stimulating effect and is therefore a legal stimulant that can increase concentration and physical performance.

People have been drinking caffeinated beverages for centuries. It is not only a natural component in coffee beans, but also in cocoa beans. It is found in
tea leaves, guarana berries and kola nuts. Caffeine is also sometimes artificially added to medicines, cosmetic products and foods (e.g. ice cream, sweets, drinks).

How does caffeine work?

It takes about 15 to 30 minutes for caffeine to take effect in the body. It enters the blood from the stomach and small intestine, is distributed throughout the body and ends up in the brain. Because caffeine crosses the blood-brain barrier. After a few hours, the substance is broken down in the liver and then excreted from the body via the kidneys.

And now specifically: caffeine works as a stimulant because it blocks a molecule that makes you tired – adenosine. Because the two molecules are similar, caffeine can occupy the adenosine receptors in the brain. And thus prevent the body from receiving tiredness signals. This effect can last for one to two hours.

At the same time, caffeine stimulates the central nervous system. It also ensures that the hormones adrenaline and cortisol are increasingly released – stress hormones that protect the body, for example, in the event of danger. They activate the body’s protective mechanisms: they constrict blood vessels, increase blood pressure and improve the supply of oxygen to the cells. The entire cardiovascular system is stimulated.

The consequence: the body becomes more alert and efficient, we can concentrate better and feel fitter.

What happens with caffeine withdrawal?

Caffeine withdrawal can produce typical withdrawal symptoms. The body reacts most strongly 12 to 24 hours after the last cup of coffee – with tiredness or a headache. It becomes harder to concentrate and you have less energy. The reason: there are suddenly a lot of free receptors for adenosine.

If you stop caffeine, a kind of rebound effect occurs, and the oxygen supply to the cells deteriorates. After a day or two, the body has recovered from the coffee withdrawal. Because caffeine can be addictive, but not nearly as strong as alcohol, nicotine or hard drugs.

It can make sense to give up coffee every now and then. Because the body reacts to the regular intake of caffeine and even forms more adenosine receptors. That means: The more caffeine we regularly consume, the worse it works. Or to put it another way: Those who drink coffee less often benefit more from the stimulant effect than long-term coffee drinkers.

Does coffee increase the risk of cancer?

The World Health Organization (WHO) classified coffee as possibly carcinogenic up until 2016. Because earlier studies came to the conclusion that there could be a connection between the consumption of coffee and bladder cancer.

However, after a working group of the International Agency for Research on Cancer had evaluated more than 1000 nutrition and cancer studies, they gave the all-clear on this point. Earlier studies had, among other things, a major shortcoming: There was no strict distinction between coffee and tobacco consumption.

Therefore, the working group came to the conclusion: There is insufficient evidence that the general consumption of coffee leads to cancer.

Is hot coffee more dangerous?

Even if there is a general all-clear when it comes to coffee and the risk of cancer: There seems to be an exception to one detail.

Because the International Agency for Research on Cancer actually recognized an increased risk of cancer in their meta-analysis – with a high drinking temperature. Specifically: According to the scientists, anyone who drinks coffee at a temperature of 65 degrees Celsius and higher increases the risk of developing esophageal cancer. Because hot coffee is considered to be the trigger for cell damage.

This risk does not only exist with coffee, but with all hot drinks.

Do coffee drinkers even live longer inside?

A classic case of confusing correlation with causation. After long-term observation, statisticians from Imperial College in London evaluated the health data of more than 500,000 people from ten European countries – and came to the conclusion: coffee drinkers live longer.

Sounds great, but it’s unclear whether it’s actually the coffee that helps you live longer. A causal relationship cannot automatically be drawn from a statistical accumulation – a problem that always arises in science. It is possible that the people who already had a higher risk of illness generally drank less coffee.

By the way, study results that examine whether coffee could protect against cancer are just as difficult to evaluate.

How much coffee is actually okay?

“Even if coffee is good for many people, medically and pharmacologically caffeine is a drug,” explains Hartmut Göbel, specialist in neurology at the pain clinic in Kiel – albeit a socially acceptable one.

The European Food Safety Authority, EFSA for short, carried out a risk assessment for caffeine in 2015. The result: A single dose of 3 mg per kilogram of body weight is harmless. That means a 130-pound woman could consume 180 milligrams of caffeine in a single dose. A cup of coffee is far from that: depending on the strength, it contains between 30 and 100 milligrams of caffeine.

According to the EFSA, women who are breastfeeding should consume a maximum of 200 mg of caffeine per day. This also applies to pregnant women, important here: the amount of caffeine should also be distributed throughout the day. Otherwise there is a risk that the fetus will grow worse.

This is what happens with too much caffeine

Anyone who consumes too much caffeine can develop cardiovascular problems, heart palpitations or cardiac arrhythmias. Others become nervous or scared, react to too much coffee by breaking out in a sweat, or sleep badly.

If you consume too much caffeine over a long period of time, you can get high blood pressure. From what amount of caffeine it comes to undesirable side effects, is individual. It depends, for example, on how used the body is to caffeine or how sensitive someone is to the substance in general.

Why do we react differently to coffee?

Researchers at Northwestern University in Illinois were able to show that why coffee works better for some than for others also depends on the genes.

Apparently, people in particular drink more coffee, the bitter substances in caffeine taste stronger than average. A result that sounds paradoxical at first – and also surprised the researchers: “One would expect that people who are particularly sensitive to the bitter taste of caffeine would drink less coffee,” says Marilyn Cornelis, who worked on the study Has.

For Cornelis and her colleagues, the results show that people who perceive the bitter substances of caffeine particularly intensively appreciate the positive properties of caffeine more. Apparently they have learned that coffee is good for you – just like you accept a bitter medicine, for example. Because bitter substances are actually a warning signal for the body.