Question of the Week

April 3, 2006

Is caffeine a part of your daily routine?

"Caffeine has many metabolic effects. For example,
* It stimulates the central nervous system.
* It releases free fatty acids from adipose (fatty) tissue.
* It affects the kidneys, increasing urination, which can lead to dehydration.
Caffeine is in coffee, tea, soft drinks, chocolate and some nuts. Whether high caffeine intake increases the risk of coronary heart disease is still under study. Many studies have been done to see if there's a direct link between caffeine, coffee drinking and coronary heart disease. The results are conflicting. This may be due to the way the studies were done and confounding dietary factors. However, moderate coffee drinking (1-2 cups per day) doesn't seem to be harmful."

The question remains: How can one know how much caffeine is in 1-2 cups of coffee? And how does this compare to the amount of caffeine a person is likely to get from other sources?

"Caffeine is ingested from many sources. In many instances people may be unaware of its presence. A standard cup of coffee contains 70-180mg caffeine depending on the strength and method of preparation. Instant coffee generally contains less caffeine than coffee prepared from ground beans. Tea contains 20-35mg per cup."

It is often difficult to know exactly how much is in a particular beverage because so many factors go into determining how much caffeine is in a drink that is brewed. When caffeine is added to a drink (where it does not occur naturally -- such as soda and energy drinks), it is easier to for those who manufacture it to have an exact idea of how much caffeine one can expect to find. Unfortunately, while someone may know the exact caffeine content, it is usually not the consumer.

"[T]he Food and Drug Administration has had a long-standing 'proposed' rule that soft drinks limit their caffeine content to no more than 65 mg per 12-ounce serving. But neither sodas nor energy drinks are required to put their caffeine content on the label. In their tests, Goldberger and his colleagues found that all 19 soft drinks they sampled contained less than -- often far less than -- the recommended 65 mg of caffeine per 12 ounces. Most of the energy drinks, however, boasted at least that much caffeine in an 8-ounce serving. A serving of one of the products had 141 mg of caffeine, or about twice the amount in a double-shot espresso drink. Others typically contained 65 to 75 mg of caffeine per 8 ounces, whereas a regular Coke or Pepsi had about 30 mg per 12 ounces. Labels on that product, and two of the other energy drinks, did state that they are not recommended for children and pregnant women.... But other groups
-- such as people with high blood pressure, heart rhythm abnormalities or anxiety disorders
-- should limit their caffeine intake as well, and the majority of the energy drinks in this study had no warning label of any kind, Goldberger noted."

Some may think that a warning label seems a bit excessive. Others disagree. Some take caffeine intentionally, while others find it hiding in various over-the-counter products. Whatever the source, too much can be dangerous.

"A browse through shelves of ingestable products sold to assist in fitness and sporting performance will reveal that many products contain caffeine, some in quite large quantities. For some the recommended daily dose includes more than 500mg of caffeine. Caffeine may be present in these products from the herbal preparation guarana, as well as being added as pure caffeine. ... Those who take these preparations without reducing their regular caffeine intake from other sources may risk developing what has been termed 'caffeinism' which is caused by toxic levels of caffeine. The symptoms include nausea, diarrhoea, indigestion, irregular heartbeat and respiration, light-headedness, jitteriness and frequent urination. These symptoms may also develop in those not habitually exposed to caffeine who ingest a moderate dose."

Most people do not generally think about "toxic levels of caffeine," however,

"Caffeine (KAF-feen) belongs to the group of medicines called central nervous system (CNS) stimulants. It is used to help restore mental alertness when unusual tiredness or weakness or drowsiness occurs. Caffeine's use as an alertness aid should be only occasional. It is not intended to replace sleep and should not be used regularly for this purpose. ... Caffeine powder and tablets are available without a prescription; however, your health care professional may have special instructions on its proper use. Citrated caffeine and caffeine and sodium benzoate are to be administered only by or under the supervision of your doctor."

Some may take caffeine to help them feel better, but few generally think of caffeine as actual medicine.

"Caffeine is also used in combination with ergotamine (for treatment of migraine and cluster headaches) or with certain pain relievers, such as aspirin or aspirin and acetaminophen. When used in this way, caffeine may increase the effectiveness of the other medicines. Caffeine is sometimes used in combination with an antihistamine to overcome the drowsiness caused by the antihistamine. Citrated caffeine is used to treat breathing problems in premature babies. Caffeine may also be used for other conditions as determined by your doctor."

Questions of the Week:
How do you know how much caffeine is okay for you? How does a person's current health status affect how much caffeine that person can safely ingest? How can you tell how much caffeine is in the products you choose? In what ways can caffeine be good for some people? How can a person tell when they have had too much?

Please email me with any ideas or suggestions.
Note: Due to increasing amounts of SPAM sent to this account, please include "QOW" in the subject line when sending me email.

I look forward to reading what you have to say.

[email protected]
Health Community Coordinator
Access Excellence @ the National Health Museum

Request Question of the Week by email 
QoW Archives: 9/2002 - 8/2003 9/2003 - 8/2004 9/2004 - 8/2005 9/2005 - 8/2006 9/2006 - present

Custom Search on the AE Site