A Coffee is undoubtedly the most commonly used and abused drug (caffeine) in North America. A naturally occurring stimulant found in the leaves, seeds or fruit of dozens of plants worldwide, caffeine is the most widely used psychoactive substance in the world.The sources of caffeine most commonly consumed include the coffee bean, the tea leaf, the kola nut, and the cocoa bean, found in some of our favorite junk foods: coffee, tea, soda, energy drinks and chocolate. Numerous pain medications also contain caffeine because it increases the ability of other drugs to do their job and decreases drowsiness side effects.
Caffeine is a Drug
The "wake-up" effect of caffeine is due to its action as a drug. Caffeine has several metabolic actions as a central nervous system stimulant; these include causing an increase in heart rate, blood pressure, respiration, gastrointestinal activity, stomach acid output, kidney function, and mental activity. Following consumption of caffeine, it is readily absorbed into the bloodstream, where its level peaks after about one hour.
How Does Caffeine Work?
The exact mechanism by which caffeine delivers its java jolt has been postulated in several theories, however according to National Geographic's January 2005 feature, "Caffeine, the World's Most Psychoactive Drug", the current consensus by scientists is that caffeine interferes with the biochemical adenosine, which acts as a natural sleeping pill. It is believed that by blocking the hypnotic effect of adenosine, caffeine prevents people from falling asleep.
In the same article, Dr. Charles Czeisler, neuroscientist and sleep expert at Harvard Medical School explains that caffeine helps people try to wrest control away from the human circadian rhythm that is hardwired in all of us, but the tradeoff has been that as a society, we are chronically sleep deprived.
Dr. Czeisler observes that the caffeine craving is a complete catch-22 in which caffeine is used to promote wakefulness to compensate for lack of sleep: "We use caffeine to make up for a sleep deficit that is largely the result of using caffeine."
Negative Effects of Caffeine
Aside from its ability to promote wakefulness, caffeine also has the desirable side effect of enhancing mood and alertness in moderate amounts. But what are the negative effects of caffeine consumption?
Heavy daily caffeine use – defined by the Mayo Clinic as more than 500 to 600 mg a day, or about four to seven cups of coffee – can cause serious problems. Even small doses may result in negative side effects depending on your body mass, history of caffeine use, and stress level. People with smaller body mass feel the effects of caffeine more intensely, as do people without a history of caffeine use and any kind of stress, physical, or psychological.
According to Dr. Elson M. Haas in Staying Healthy with Nutrition (2006), coffee abuse can result in cardiac sensitivity, abnormal heartbeats, anxiety and irritability, stomach and intestinal irritation, insomnia, and such withdrawal symptoms as fatigue, headaches, and depression.
by Johneen
