Answer: A maximum dose of 200 mg of caffeine at once and 400 throughout the day, for a healthy adult (count 200 mg max per day for a pregnant woman). If we exclude the consumption of sodas and other energy drinks, this implies up to 4 to 5 coffee mugs throughout the day (and no more than one and a half at a time). In addition, there is a risk of “deleterious effects” on health but people prone to stomach disorders or heart problems should be careful before this limit. All this varies depending on several factors: contrary to popular belief, filter coffee contains more caffeine than espresso and must also take into account the metabolism of each. This is also why some people can drink coffee before going to bed without risk of insomnia. Nature is unfair.