500 ml of caffeine per day is safe.

German chemist Friedrich Ferdinand Runge was the first to isolate caffeine and explain its adverse effects. Since then, caffeine has worried coffee drinkers, doctors and scientists. However, the initial study focused on the adverse health effects of excessive caffeine consumption, with little assessment of the positive health effects of moderate coffee intake (not just caffeine). In 1819, the young Runge began chemical experiments and discovered the effects of belladonna extract on the eyes. In 1820, long told his good friend Goethe about his findings, and Goethe encouraged him to analyze the coffee. A few months later, Runge first extracted caffeine. Joanne Wolfgang Goethe is a German poet, novelist, humanist, theorist, painter and politician who loves coffee. Goethe's influence spread throughout Europe, and his works were the main source of inspiration for music, drama, poetry and philosophy for a whole century. Caffeine was discovered by humans because of Goethe's encouragement.

Caffeine is the most thoroughly studied ingredient in food. The effects of caffeine on human health have been well studied. Modern science knows almost all the advantages and disadvantages of caffeine, but little is known about the relationship between coffee and human health. Past studies have shown that coffee is very harmful to human health because it contains caffeine. In almost every published scientific article on coffee, the focus is on caffeine content and the effects of purified caffeine on people or animals. Caffeine is considered to be the main mental stimulant in coffee, but this is not the case. Today, every knowledgeable doctor, scientist, and coffee drinker can be absolutely sure that it is safe to consume the right amount of caffeine (up to 500 milligrams), which is equivalent to 3-4 cups of coffee. A daily intake of 500-600 milligrams has a certain health risk. In 1987, the Food and Drug Administration (FDA) reaffirmed its positive role. Scientific experiments have shown that caffeine in carbonated drinks does not have any side effects on the human body. The National Academy of Sciences, the Scientific Research Council and the General Office of Surgeons reported that there was no correlation between moderate caffeine intake and increased health risk. Frequent coffee drinkers who abruptly stop taking caffeine can cause mild withdrawal symptoms (such as drowsiness or occasional headaches), but do not develop addictive behavior. Caffeine citrate is used medicinally at a dose of 20 mg / kg for the treatment of asphyxia in premature infants. Caffeine is also used to relieve headaches and migraines after spinal cord puncture.