The main thing to focus on is caffeine. It affects the nervous system, heart, and overall well-being. According to the World Health Organization and other studies, a dose of up to approximately 400 mg of caffeine per day is considered safe for a healthy adult.

What does this mean in practice?

One serving of espresso (about 30 ml) contains approximately 60-80 mg of caffeine.
A regular cup of coffee (200-250 ml) contains approximately 80-120 mg, depending on the strength.

That is, on average:

4-5 servings of espresso per day is an acceptable intake
or 3-4 cups of regular coffee

But there are important nuances.

Firstly, everyone's sensitivity varies. For some, just one cup is enough to feel anxiety or a racing heart. Secondly, it's important to consider the timing - coffee in the afternoon can impair sleep, even if you don't immediately notice.

It's also worth remembering that coffee isn't just caffeine. It can affect the stomach, especially if you drink it on an empty stomach, and can sometimes increase stress if the body is already overloaded.

Interestingly, in moderation, coffee can even be beneficial: it improves concentration, increases productivity, and may reduce the risk of certain diseases.

The bottom line is simple: coffee is a pleasure, but in balance. If you feel good, sleep well, and don't experience any unpleasant symptoms, then you've found your balance.