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© Copyright 2011, Pearson Education, Inc. All rights reserved. Chapter 11 Caffeine.
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Transcript of © Copyright 2011, Pearson Education, Inc. All rights reserved. Chapter 11 Caffeine.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Caffeine • Caffeine belongs to a family of stimulant
drugs called xanthines.
• It is found in coffee, tea, chocolate, many soft drinks, and some medications.
• Other xanthines are theophylline (found in tea) and theobromine (found in chocolate).
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Coffee
• Coffee drinking originated in the Middle East and later was introduced to England in the seventeenth century.
• Coffee houses in Britain and in colonial America sprang up as establishments where political and social discussions could be held.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Coffee • Today’s coffee comes from a mixture of
arabica and robusta beans, imported largely from Brazil, Colombia, Indonesia, and several nations in Africa.
• On average, a 5-ounce cup of coffee contains roughly 100 mg of caffeine, the actual level being determined by the type of coffee beans used and the method of brewing.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Tea
• Tea drinking originated in China and later was introduced to Europe by Dutch traders in the early seventeenth century.
• It became most popular in Britain and Russia.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Tea
• Today, tea consumption is greatest in Britain and Ireland.
• On average, a 5-ounce cup of tea contains roughly 60 mg of caffeine, the actual level being determined by the method of brewing and brand.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Chocolate
• Chocolate originated in pre-Columbian Central America and was introduced into Europe by the return of Cortés to Spain in 1528.
• Its popularity spread across Europe in the seventeenth century.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Chocolate
• By the 1880s, techniques for producing present-day milk chocolate had been perfected.
• The caffeine level in chocolate is relatively low, roughly 6 mg per ounce.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Soft Drinks
• Caffeinated colas have most of the caffeine content added to the beverage during production.
• Levels of caffeine in these beverages are approximately 38–45 mg per 12 ounces.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Caffeine from Medications
• Like drugs, caffeine and other xanthines are stimulants of the CNS and of peripheral musculature.
• Theophylline, in particular, has a strong bronchodilating effect and is useful for treating asthmatic conditions.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Caffeine as a Drug • The behavioral effects of caffeine can be
characterized principally as a reduction in fatigue and boredom, as well as a delay in the onset of sleep.
• Recent evidence suggests that caffeine might lower the risk of developing Parkinson’s disease in men.
• A comparable protective role in women is currently uncertain.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Caffeine as a Drug
• Health risks from moderate consumption of caffeine are not clinically significant, except for the adverse effects on fetal development during pregnancy, the development of bone loss among the elderly, a possible adverse effect on the cardiac condition of patients already suffering from cardiovascular disease, and the aggravation of panic attacks among patients with this disorder.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Caffeine as a Drug
• Continued consumption of caffeine produces tolerance effects; when caffeine consumption ceases, withdrawal symptoms are observed.
• High levels of caffeine consumption can produce toxic effects, although deaths are extremely rare.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Kids and Caffeine
• Young people in the United States ingest increasingly large quantities of caffeine through the drinking of caffeinated soft drinks and coffee.
• The actual dosage level is substantial, since body weight is less than that of an adult.
© Copyright 2011, Pearson Education, Inc. All rights reserved.
Kids and Caffeine
• Health concerns regarding caffeine consumption in this population include potential deficiencies in calcium and phosphorus for normal bone growth as well as behavioral problems such as insomnia, nervousness, and anxiety.
• The current popularity of highly caffeinated “energy drinks” has added to these problems.