Incidence of caffeine withdrawal. Blind experimental studies in healthy normal caffeine consumers who abstain for „ 24 hours indicate that the incidence of withdrawal headache is about 50%. When all withdrawal symptoms are considered, the incidence of caffeine withdrawal is higher. In a population-based random digit dial telephone survey study, 40 to 70% of individuals who tried to quit caffeine use reported experiencing withdrawal symptoms.
Many caffeine consumers may be unaware of their physical dependence on caffeine because their frequent habitual consumption precludes a period of sustained abstinence (e.g. 2 days). Furthermore, relatively low doses of caffeine (e.g. as little as 25 mg) can partially suppress withdrawal symptoms. Thus, some people may report never experiencing withdrawal because they unknowingly consumed small amounts of caffeine on days they thought they had been caffeine free. Finally, caffeine withdrawal symptoms (e.g., headache, nausea, muscle aches) may be misattributed to other causes or ailments (e.g., viral infection).
