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Some of us feel a little guilty about our habitual consumption of coffee along with its caffeine content. Are these feelings warranted? Haven't health advocates said these are bad substances? Should we cut down? The answer could be "perhaps" , "it depends" or "you are the best one to decide."
Coffee comes from coffee beans, which are the dried seeds of the berries of coffee trees; coffee trees are grown primarily in Latin America, Africa and Indonesia. Coffee contains extremely small amounts of a few vitamins and minerals, but also contains several phytochemicals, including caffeine, which is biologically active.
Caffeine is considered a stimulant and is found naturally in coffee, tea, and chocolate, and is an added ingredient in some soft drinks and other foods. This substance has been extensively researched during the past twenty years. The U.S. Food and Drug Administration classified caffeine as Generally Recognized As Safe (GRAS) in 1958. The position of the American Medical Association also suggests that moderate use of caffeine is not a health concern, stating that "Moderate tea or coffee drinkers probably need have no concern for their health relative to their caffeine consumption provided other lifestyle habits (diet, alcohol consumption) are moderate, as well."
What is moderate caffeine consumption? About 300mg or the amount of caffeine in 3 cups of coffee is considerate a moderate intake by most experts. However, what is moderate for one person may not apply to another based on certain health problems or differences in tolerance to the substance. It is always a good ideal to consult with your health care provider if you have concerns about what is an acceptable amount for you. Different people have different sensitivities to caffeine; some can have several cups of coffee without heightened nervousness, jitteriness or the inability to sleep when it is consumed late in the day. Others have a decreased tolerance and develop these symptoms with lower intakes. Caffeine doesn't accumulate in the body and is usually excreted within several hours after it is consumed.
Caffeine is definitely a stimulant and has been shown to increase alertness, and enhance performance of certain mental and physical tasks or work. Most people are not aware that caffeine enhances athletic endurance at levels as low as 3 cups or less. Caffeine is considered a "restricted substance" at the Olympic level, the current limits of use which is equivalent to about 3 to 6 cups of coffee a day may not be sufficient, according to a report published in The Journal of Sports Medicine and Physical Fitness. The authors noted that even fairly small amounts of caffeine enhanced endurance performance. Jonathan Geiger, a faculty member at the University of Manitoba in Winnipeg and chair of the Drugs and Sports steering committee of the Drugs and Sports Medicine Council of Manitoba says it is a matter of where to draw the line with athletes. Caffeine, just as other substances has the potential for abuse, not only at the Olympic level but also in high school athletics.
And what is known about coffee and cancer? According to the landmark report Food, Nutrition and the Prevention of Cancer: a global perspective, published by the World Cancer Research Fund and the American Institute for Cancer Research, most evidence suggests that coffee consumption has no relationship with cancer risk.
Many years ago, scientists at Ohio State University reported that caffeine increased the risk of fibrocystic breast disease (FBD), which is a condition with benign fibrous lumps in the breast. Although many women report that eliminating caffeine-containing foods and beverages decreases their symptoms, several later studies have not confirmed the association between FBD and caffeine. Both the American Medical Association's Council on Scientific Affairs and the National Cancer Institute published reports stating there is not an association between caffeine intake and the incidence of fibrocystic breast disease.
In response to the earlier report about a possible association between caffeine or coffee and FBD, a number of studies were launched to determine whether caffeine was a risk factor for breast cancer. Overwhelmingly most of the studies found no relationship between coffee intake and breast cancer. The panel evaluating all of the studies found that there is convincing evidence that there is no relationship between coffee drinking and breast cancer.
In 17 studies looking at coffee consumption and colorectal cancer, ten studies showed decreased risk with higher consumption of coffee, three increased risk and four no association. The protective effect seemed to be apparent only at the highest levels of consumption. There have been some reports that the antioxidants present in coffee may offer some protection. The evidence on the protective effect is, as yet, insufficient.
The bottom line is enjoy caffeine containing beverages and food, but remember our favorite word moderation.
SOURCES OF CAFFEINE
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Food or Beverage
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Average
(milligrams of caffeine) |
Range*
(milligrams of caffeine) |
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Coffee (8 oz. Cup) |
|
|
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Brewed, drip method |
85 |
65-120 |
|
Instant |
75 |
60-85 |
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Decaffeinated |
3 |
2-4 |
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Espresso (1 oz. cup) |
40 |
30-50 |
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Teas (8 oz. cup) |
|
|
|
Brewed, major U.S. brands |
40 |
20-90 |
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Brewed, imported brands |
60 |
25-110 |
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Instant |
28 |
24-31 |
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Iced (8oz. glass) |
25 |
9-50 |
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Soft drinks (those containing caffeine) |
24 |
20-40 |
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Cocoa beverage (8oz.) |
6 |
3-32 |
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Chocolate milk beverage
(8 oz.) |
5 |
2-7 |
|
Milk chocolate candy (1 oz.) |
6 |
1-15 |
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Dark chocolate, semi-sweet (1oz.) |
20 |
5-35 |
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Baker’s chocolate, unsweetened (1oz.) |
26 |
26 |
|
Chocolate-flavored syrup (1oz.) |
4 |
4 |
*Due to brewing method, plant variety, brand, etc.
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