Caffeine kick with health risks

Caffeine is almost ubiquitous in everyday life. It is found in the typical morning cup of coffee, in black tea, in cola, in energy drinks and even in chocolate. "In moderate amounts, caffeine has a stimulating, positive effect," explains biologist Dr Anke Ehlers in the new episode of ‘Risk’ – the science podcast from the German Federal Institute for Risk Assessment (BfR). In high doses, however, caffeine can cause sweating, anxiety and heart rhythm disorders, as well as affect the growth of the foetus in the mother's womb. In extreme cases, severe overdoses from food supplements can even be fatal.

The general rule for adults is that a single dose of 200 milligrams of caffeine is not considered harmful to health. This is roughly equivalent to two cups of coffee, two cans of energy drink, four cups of tea, or five cans of cola. Spread out over the course of a day, up to twice that amount – or 400 milligrams of caffeine per day – is considered unproblematic. However, the level at which adverse effects may actually occur varies from person to person. And those who, for example, regularly drink a lot of coffee tend to develop a higher tolerance level. However, they then need more coffee to still notice the positive effects.

Particular caution is advised when taking food supplements containing caffeine, which are sometimes used to enhance performance in sports. In this case, it is essential to follow recommended dosage instructions, otherwise overdosing can easily occur. "In particular, pure caffeine powder in loose form is problematic," says BfR expert Ehlers: "It is in such a high concentration that you just can't measure it with a kitchen scale." The safe amount of 200 milligrams or 0.2 grams corresponds here to about a pinch. And just one or two teaspoons can be fatal.

For children and adolescents, the amount of caffeine that is still harmless to health is determined by body weight: a daily intake of 3 milligrams of caffeine per kilogram of body weight is therefore acceptable.

For younger children in particular, caffeine is mainly ingested through chocolate. However, to consume a dangerous amount of caffeine from sweets, a child would have to eat or drink a very large amount in a very short time. "Taking a four-year-old child weighing around 17 kilograms as an example, they could just consume about 50 milligrams of caffeine." says Ehlers. This amount is roughly equivalent to the caffeine content of two and a half bars of milk chocolate or half a litre of cola. ‘Of course, this is not a recommendation, not least because of the high sugar content, but rather the amount that is just safe in terms of caffeine concentration.

Energy drinks contain about the same amount of caffeine as coffee. A 250-millilitre can contains an average of about 80 milligrams of caffeine. For teenagers, therefore, just three cans is enough to exceed the safe amount. "Mixing energy drinks and alcohol can intensify the effects", says Ehlers. "Both the caffeine and the alcohol affect the cardiovascular system and can cause heart rhythm disorders. When both factors come together, these negative effects could intensify."

Link to the full podcast episode (available only in German):

https://podcast.bfr.bund.de/7-koffein-kick-mit-risiko-007

Quotes and sound bites from the podcast episode may be used freely provided the source is acknowledged.

Further information on melatonin on the BfR website:

Even small amounts of highly concentrated caffeine powder can cause severe poisoning
https://www.bfr.bund.de/cm/349/even-small-amounts-of-highly-concentrated-caffeine-powder-can-cause-severe-poisoning.pdf

Frequently asked questions on Caffeine and Foods Containing Caffeine, including Energy Drinks
https://www.bfr.bund.de/en/frequently_asked_questions_on_caffeine_and_foods_containing_caffeine__including_energy_drinks-194902.html

About "Risko – Der BfR-Podcast"

Daily newspapers, online news and social media posts are constantly warning of new health hazards: Plasticisers in sun creams, microplastics in the body or alleged harmful substances in food. What is actually true about these alleged hazards? How great is the risk for me personally? In our podcast "Risiko", we get to the bottom of such topics. In a relaxed, scientifically sound and easy-to-understand way. "Risiko" is released about once a month. In casual discussions with experts, we talk about real and perceived health risks posed by food, chemicals or consumer products. The podcast is only available in German.
 

About the BfR

The German Federal Institute for Risk Assessment (BfR) is a scientifically independent institution within the portfolio of the Federal Ministry of Food and Agriculture (BMEL) in Germany. The BfR advises the Federal Government and the States (‘Laender’) on questions of food, chemicals and product safety. The BfR conducts independent research on topics that are closely linked to its assessment tasks.

This text version is a translation of the original German text, which is the only legally binding version.