WHETHER WAKING up to the aroma of freshly brewed coffee, enjoying lunch with a cold soft drink or relaxing in the evening with a cup of tea, these daily pleasures often have a common ingredient - caffeine.
Today, huge numbers of people everywhere consume caffeine to change or enhance the way they feel and act. What are the origins of caffeine? Are there any health benefits from its ingestion? Is there a down side?
SOURCES OF CAFFEINE
Caffeine is a naturally occurring substance found in the leaves, seeds and fruits of at least 63 plant species worldwide, and is part of a group of compounds known as methylxanthines. The most commonly known sources of caffeine are coffee, cocoa beans, kola nuts and tea leaves.
The amount of caffeine in food products varies depending on the serving size, the type of product and preparation method. The table at right provides some valuable information on products that contain caffeine and how much.
PHYSIOLOGICAL EFFECTS OF CAFFEINE
Caffeine is a pharmacologically active substance and, depending on the dose, can be a mild central nervous system stimulant. The pharmacological effects of this ingredient are transient, usually passing within a few hours. Caffeine does not accumulate in the body over the course of time and is normally excreted within several hours of consumption.
| ITEM | | TYPICAL | RANGE |
| Coffee (8-oz cup) | Brewed, drip method | | 85 | 65-120 |
| | Instant | | 75 | 60-85 |
| | Decaffeinated | | 3 | 2-4 |
| | Espresso (1-oz cup) | | 40 | 30-50 |
| Teas (8-oz cup ) | Brewed, major U.S. | | 40 | 20-90 |
| brands | | | 60 | 25-110 |
| | Brewed, imported brands | | 28 | 24-31 |
| | Instant | | 25 | 9-50 |
Iced (8-oz glass)
| Some soft drinks (8 oz) | 24 | 20-40 |
| Cocoa beverage (8 oz) | 6 | 3-32 |
| Chocolate milk beverage (8 oz) | 5 | 2-7 |
| Milk chocolate (1 oz) | 6 | 1-15 |
| Dark chocolate, semi-sweet (1 oz) | 20 | 5-35 |
| Baker's chocolate (1 oz) | 26 | 26 |
| Chocolate-flavoured syrup (1 oz) | 4 | 4 |
