• Caffeine is the most widely consumed stimulant in the world.
  • It is consumed in the form of coffee and tea.
  • At present there is no scientific data for promoting or discouraging coffee and/or tea consumption in the daily diet.
  • Short-term benefits include mental alertness and improved athletic performance.
  • Short-term adverse effects include headache, anxiety, tremors and insomnia.
  • Long-term adverse effects include generalized anxiety disorder and substance abuse disorders.
  • Long-term benefits are dose-dependent. Caffeine is associated with a reduced risk of Parkinson’s disease, Alzheimer disease, alcoholic cirrhosis, and gout. Coffee, both caffeinated and decaffeinated, is also associated with a lower risk of type 2 diabetes.
  • Heavy coffee intake may trigger coronary and arrhythmic events in susceptible individuals, although coffee intake is not considered a long-term risk factor for myocardial disease.
  • Most studies show a modest inverse relationship between coffee consumption and all-cause mortality.
  • Caffeine withdrawal is a well-documented clinical syndrome with headache being the most common symptom. (Source: Uptodate)