Wednesday, May. 05, 2010

Ask the Doctor: Myths about caffiene

Question: My sister insists that drinking coffee can prevent certain kinds of cancer. Is there any truth to this? Can the caffeine in coffee be considered an addictive substance?

L.S., Chowchilla

Answer: There are a number of myths attributable to caffeine. The idea that an individual can become "addicted" to caffeine depends on your definition of "addiction." Although caffeine is a central nervous system stimulant, it usually does not cause a threat to one's economic, social nor physical health. However, the regular use of caffeinated beverages (and food products that contain caffeine) may lead to mild "dependence." Individuals that ingest a significant amount of daily caffeine, and who abruptly stop, may experience withdrawal symptoms for a few days; however, this is not considered to be as harmful as drug-seeking behaviors, such as drugs or alcohol. Symptoms of withdrawal may include headache, irritability, mood change, etc. I would not consider dependence on caffeine or coffee an "addiction."

The relationship between cancer and caffeine is not totally clear. However, there seems to be some evidence that caffeine may provide some protective effects against certain cancers. Recently, a study revealed that women who drank more than 2 and a half cups of coffee a day were less likely to develop endometrial cancer (cancer of the uterus), than women who did not drink any coffee. Further research is needed to substantiate other cancer prevention linkage.

The bottom line: Although caffeine has relatively few proven health benefits, it has been linked to some limited positive health effects. The important thing to realize, is that moderate amounts of caffeine, about 300 milligrams, equivalent to about 3 cups of coffees a day, does not seem to cause any harm to most healthy adults, with no underlying medical problems.