For many Notre Dame students, the semester begins well, with intentions of reading a little every day, staying on top of the workload and ultimately facing finals after only a little brushing up. But on both ends of fall break, the heart of the midterm, these intentions change as quickly as the leaves turn color.

While teachers increase the workload and tests, Acoustic café and Thursday night movies at Cushing become harder to resist. Serious studying is put off until the night before a test, and many Notre Dame students rely on a caffeine buzz to help them through the night.

The popularity of caffeine on the Notre Dame campus is reflective of a similar trend throughout the world. According to the Way Pages (www.plgrm.com/health/C/Caffeine.htm), annual world consumption of caffeine is about 120,000 tons, which is equivalent to 70 mg of the drug a day for each inhabitant. Fifty-four percent of this total consumption is in the form of coffee, while 43 percent is derived from tea. Americans consume about 210 mg of caffeine a day. About 60 percent of United States' consumption is in the form of coffee, with tea and soft drinks each accounting for 16 percent of the total.

Caffeine is the world's most popular drug. The white, bitter-tasting, crystalline substance was first discovered in coffee in 1820. Caffeine was then isolated from tea leaves in 1827 and named "theine" because it was believed to be a distinctly different compound from the caffeine in coffee. Coffee began to be popular in Europe in the 17th century. By the 18th century, plantations had been established in Indonesia and the West Indies.

Caffeine is a mild stimulant, and when consumed, makes one feel more awake and alert. A high dose, however, may prevent sleep and lead to jittery feelings. Tea, coffee and soft drinks are the three major sources of caffeine. Caffeine also occurs in cacao pods and therefore can be found in cocoa and chocolate products. Each eight-ounce cup of coffee can provide approximately 65 mg to 115 mg of caffeine, but the exact amount varies widely according to cup size, method of preparation and amount of coffee used.

Generally, cups prepared from instant coffee contain less caffeine, and cups prepared by drip methods contain more caffeine. A cup of tea usually has about 60 mg of caffeine and a soft drink may contain between 30 mg and 60 mg of caffeine. A cup of hot chocolate contains about 4 mg caffeine, and a chocolate bar has between 5 and 60 mg, the amount of caffeine increasing with the quality of the chocolate. This stimulant is an ingredient of certain headache pills (30-65 mg). It is also the main ingredient of non-prescription "stay-awake" pills (100-200 mg).

On campus, caffeine is provided at virtually all food establishments. Starbucks can be found at Reckers, while gourmet coffees can be found at Waddicks in O'Shaughnessy. At Greenfields, located in the Hesburgh Center for International Studies, freshly ground coffees, cappuccino and espresso drinks are featured daily. Allegro, on the lower level of LaFortune, the Common Stock Sandwich Co. in the Business School and Irish Café, located on the lower level of the Law School, also serve gourmet coffee and espresso drinks.

Many students don't realize that caffeine is a stimulant, and dependence on it can develop as easily as it can with any other drug. Regular use of more than 350 mg of caffeine a day has been proven to cause physical dependence. Interruption of the regular use produces a characteristic withdrawal syndrome, the most noticable feature of which is an often severe headache that can be relieved by taking caffeine.

Absence of caffeine, furthermore, makes regular users feel irritable and tired. Relief from these withdrawal effects is often given as a reason for continuing to consume caffeine. A person who stops his or her caffeine intake suddenly may experience irritability, headache and lethargy. Therefore, even people who ingest low or moderate amounts of caffeine should taper off their consumption over a period of time rather than abruptly stopping.

Caffeine taken in beverage form begins to reach all body tissues within five minutes. Peak blood levels are reached in about 30 minutes. Many Notre Dame students take advantage of caffeine's effects on sleep and brain activity. Consumption of the stimulant before bedtime delays sleep onset, giving students an opportunity to study.

But caffeine also shortens overall sleep time and reduces the depth of sleep. After using caffeine, sleepers are more easily aroused, move more during sleep and report a reduction in the quality of sleep. Caffeine stimulates the brain and behavior. Use of 75 to 150 mg elevates neural activity in many parts of the brain, postpones fatigue and enhances performance at simple intellectual tasks and at physical work that involve endurance but not fine motor coordination.

"Though extensive doses of caffeine will lead to a huge crash, I stand by the belief that caffeine is a necessary part of college life. Whether it's a huge cup of coffee, a six-pack of Mountain Dew or a few No-Doz, caffeine provides the perfect pick-me-up when faced with a paper deadline, a late night of studying or one of the more boring classes on campus," said Crissy Manary, a sophomore and admitted caffeine-addict. "I don't deny that I have an addiction. Experiencing headaches, the shakes and depression during a withdrawal isn't fun, but honestly, I need the caffeine and there are worse addictions to have — smoking, for example. When professors stop assigning 40-page research papers to write, I'll switch to decaf. I promise."

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