The Effects of CaffeineWorks Cited Not IncludedCaffeine has played a central role in many cultures. Coffee was first discovered over 1,000 years ago and about 75% of Americans drink it regularly. Despite the passage of thousands of years, the biological effects of coffee and its main active ingredient, caffeine, are still controversial. Caffeine is the most widely used stimulant drug in the world, commonly ingested in the form of coffee, tea, soft drinks, and chocolate. (Honig) Caffeine is derived from a bean or tea leaf and can be found in the seeds or fruits of more than 60 species worldwide. (American Academy) Caffeine has many effects and it is disputed whether caffeine is beneficial or harmful overall. xanthine present (precursor to uric acid, often present in urine) used as a central nervous system (CNS) and respiratory stimulant, or as a mild diuretic. Other xanthine derivatives include theophylline and the bronchodilator theobromine, a compound found in cocoa and chocolate. Caffeine is a mild but direct stimulant at all levels of the CNS that also accelerates the heart and cardiovascular system. The related xanthine, theophylline, shares these characteristics and is used in the treatment of lung diseases. Caffeine and theophylline are CNS stimulants, with theophylline exerting more dramatic effects than caffeine at higher concentrations. Caffeine also stimulates the medullary respiratory center and relaxes bronchial smooth muscles. Caffeine stimulates... middle of article... blemishes, asthma, fibromyalgia, chronic fatigue, autoimmune diseases and rheumatoid arthritis. (James) Numerous studies have suggested a relationship between chronic caffeinating and a number of diseases. However, proof of cause and effect is difficult to prove due to lifestyle variables among study subjects (e.g., smoking, alcohol consumption, exercise), differences in genetic inheritance , the form of caffeine consumption (coffee, tea, soda) and the presence of other biologically active substances in the drink. (Brice) Caffeine consumption certainly has side effects, some negative, others positive, but it is clear that when taken in moderation, caffeine is never harmful to your health. However, caffeine consumers should be aware of withdrawal and stay up to date with the latest research on caffeine..