Excessive intake of caffeine has some drawbacks that should not be underestimated. The daily dose indicated is 300 mg (equal to 3 cups of espresso), but it should be remembered that this limit can also be reached through the consumption of tea, dark chocolate, and Coca-Cola. Excessive intake of caffeine can cause a list of even serious side effects, such as: tachycardia, esophagitis, insomnia, abdominal pain, acidity, anxiety, and tremors.