Caffeine is a naturally occurring psychoactive stimulant. In humans, caffeine stimulates the central nervous system and the body’s metabolism, and also has a mild diuretic effect. The U.S. Food and Drug Administration lists caffeine as both a drug and a food additive. Unlike many other psychoactive drugs, caffeine is legal, socially accepted and virtually unregulated.
Caffeine Tolerance and Withdrawal
Caffeine consumers, like some users of other psychoactive drugs, might develop tolerance to its stimulant, metabolic and diuretic effects. Tolerance is a physical phenomenon in which the user’s body gets used to a substance and requires more of it to get the same level of effect. At this point, the user is considered physically addicted to the substance. If the user consumes less of an addictive substance such as caffeine, he might experience withdrawal symptoms.
Caffeine tolerance develops rather quickly, and symptoms of caffeine withdrawal include fatigue, drowsiness, headache, depression, irritability, difficulty concentrating, insomnia, nausea, vomiting and muscle pain or stiffness.
Research on Caffeine Withdrawal
In a study published in 2004, Johns Hopkins University researchers found that the onset of caffeine withdrawal occurred within 12 to 24 hours of stopping caffeine dosing. The peak withdrawal symptoms occurred in one to two days. The researchers found that the symptoms were gone within from two to nine days. The intensity of the symptoms was proportional to the daily dose of caffeine.
Reducing or Eliminating Symptoms of Caffeine Withdrawal
The duration and severity of the withdrawal symptoms might be mitigated by gradually reducing caffeine consumption. For heavy coffee drinkers, substituting tea might help in tapering off caffeine. Take into consideration all possible sources of caffeine: pain medications, chocolate, soft drinks, diet pills and energy drinks. Some beverages and nutritional supplements might contain caffeine in the form of yerba mate, kola nut or guarana.
Kathleen Zelman, R.D. and a nutritionist in Atlanta, recommends the "25 percent solution," which suggests that withdrawal symptoms can be avoided or attenuated by reducing caffeine consumption by 25 percent each week until you are caffeine-free.