Many people rely on caffeine to wake them up or to get a boost of energy when they're feeling down. Acting as a stimulant, caffeine not only improves concentration and attention, but also stops fatigue (Stick 1). Considered the most commonly used psychoactive drug in the world, approximately 90% of adults use it daily (“MedicineNet.com” 1). But do caffeine buyers really stop to evaluate the possible harmful effects on their bodies? Health fears like this are not recent. In fact, they have been going on for over 100 years. In 1911, the United States government sued the Coca-Cola company for making its drinks dangerous to the health of others (Lovett 2). Even though the Coca-Cola company won, it shows that people care about what they put in their bodies, even if it helps them stay awake to finish their homework. Not everyone will experience the same effects of caffeine. Some people seem more sensitive to caffeine than others (Rigor 1). While some experience side effects after just one cup of coffee or tea, others don't notice the same effects until after perhaps four or five cups. Although caffeine has benefits, many negative aspects also exemplify its stimulating action. Drinking even small amounts of caffeine every day develops harmful effects on the body and health of most people. According to Walter Willett, professor of epidemiology and nutrition at the Harvard School of Public Health, one of the risks associated with caffeine consumption is an increase in bone fractures because caffeine causes calcium. loss which then affects bone density (Lovett 3). In most cases, this effect occurs in people who drink four or more cups of caffeine per day. Too much caffeine introduced into the body causes bones to break more easily than if you drank no caffeine at all. At the center... of the paper... people's bodies and health. Works Cited Goodman, Ericka. "What Caffeine Can Do for You. (Anti-Fatigue Tactics)." Redbook February 2003: 48. Gale Power Search. Network. February 26, 2012Lovett, Richard. “Demon Drink.” New Scientist (London, England) vol. 187, No. 2518. September 24, 2005: 38-41. SIRS Problem Researcher. Network. February 26, 2012."MedicineNet.com." MedicineNet. Network. February 26, 2012. Staff, Mayo Clinic. “Caffeine: How Much is Too Much?” Mayo Clinic. Mayo Foundation for Medical Education and Research, 9 March 2011. Web. 26 February 2012. Stroh, Michael. “Just one cup a day is enough to attract coffee drinkers.” Los Angeles Times (Los Angeles, California). November 29, 2004: F3. SIRS Problem Researcher. Network. February 26, 2012.Weinberg, Linda. "Coffee break or caffeine fix? Pros and cons of stimulant drinks." Environmental nutrition. November 2000: 1+. SIRS Problem Researcher. Network. February 26 2012.