From a nutritional point of view, coffee is not an indispensable food for our body, however, some substances contained in it cause beneficial effects to some organs of the human body. The habit of consuming it daily does not lead to addiction even after long periods however, as with any food, it is necessary not to abuse it if you do not want to get undesirable effects such as tachycardia.
Coffee contains caffeine which, in combination with caffettaninnic acid, acts mainly on the nerve centers causing a general sense of well-being, spurring one to be more alert and active both physically and mentally. Effects also occur on the lungs with dilation of the bronchi and lung ventilation, on skeletal muscles by enhancing the capacity for muscle contraction, on the heart as a cardiotonic, on the stomach walls by promoting the secretion of gastric juices which improves the digestive process, etc.
Caffeine is found in both the seed and leaves of the coffee plant but also in tea plants, cocoa, maté, etc. A cup of coffee contains between 50 and 150 mg of caffeine: the difference depends on how the coffee is prepared. For example, filtered coffee contains more caffeine than espresso because during the slow filtering process the water dissolves more caffeine from the coffee powder than is released by the typical espresso preparation, which instead involves a very fast passage of the pressed water through the coffee. It should be kept in mind that the actions on the heart are entirely secondary and are not detectable in the usual doses of 2-3 cups
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