Note the caffeine content

Can drinking too much coffee be harmful?

Coffee can have a stimulating effect, but can also make you nervous, aggressive and anxious.

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Karin B. (42): "I regularly drink three to four cups of coffee a day. But I keep hearing that too much coffee is unhealthy and dehydrating. What's the truth?". A nutrition expert explains.

With moderate consumption (single doses of up to 200 mg), caffeine is said to have positive properties such as relaxation, energy, improved concentration and increased alertness. "Caffeine can have a negative effect from high to very high doses (single doses of 400 to 800 mg of caffeine). It can then trigger nervousness, anxiety, aggression, sleep disorders and palpitations, for example," emphasizes Dr. Marlis Gruber, nutritionist at "forum.ernährung heute".

How much is tolerable?
According to an assessment by the European Food Safety Authority (EFSA), the total daily amount of caffeine that is safe depends on body weight. For children (3-10 years) and adolescents (10-18 years), 3 mg/kg body weight is the daily tolerable upper limit. For adults, 400 mg of caffeine per day (around 5.7 mg/kg body weight) is completely safe.

Cola and energy drinks also contain a lot of caffeine.

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Dr. Gruber: "All sources must be taken into account for the total intake. Not only coffee, cola and energy drinks contain caffeine, but also black and green tea, iced tea and chocolate. Although the caffeine content of coffee and chocolate varies greatly, you don't need to worry if you drink up to five cups of coffee a day." An espresso (and therefore also a cappuccino or latte macchiato) has around 40 mg of caffeine, as does a 250 ml bowl of green or black tea.

The idea that coffee is a fluid robber is based on a misconception. According to the German Nutrition Society (DGE), drinks containing caffeine can be included in the fluid balance like any other drink. This is because large amounts of coffee only lead to increased water excretion in people who are not used to it. For people who drink coffee more often, the diuretic effect is minimal. The traditional glass of water with coffee is still useful if you tend to drink too little in general.