Caffeine withdrawal: Cost or benefit?

Abstract

Caffeine ingestion has been shown to enhance alertness and performance. However, caffeine ingestion before bed has also been shown to lower the quality and quantity of sleep. For several reasons, including improved sleep hygiene to prevent or treat insomnia, caffeine withdrawal may be suggested. Many studies have shown negative effects during the first few days of caffeine withdrawal including headaches, lethargy, and irritability. Very few studies have continued observations beyond these immediate negative effects to determine the longer term effects. In other words, are individuals benefited or impaired given a longer period free of caffeine compared to the normal caffeine consumption period? The present study investigated a period of several weeks following caffeine withdrawal. Participants were 23 healthy young adult caffeine consumers. In addition to a caffeine consumption diary they recorded subjective evaluations of their day at 6 pm each day on a web based survey. The evaluations included headache symptoms, alertness, fatigue, moods, sleep, and overall quality of daily functioning. Measures were collected daily for a baseline week of normal caffeine consumption, a week of gradual withdrawal, and four additional weeks of caffeine abstention. Repeated measures statistical analyses compared means for the baseline week, withdrawal week and the fourth week free of caffeine. During the week of withdrawal reported headaches and sleep length increased while alertness and overall day quality decreased compared to baseline caffeine consumption. However, by the last week all of these measures had returned to be comparable with the baseline week and in most cases were marginally but not significantly better than baseline week. From this initial pilot study of the longer term subjective effects of caffeine withdrawal it appears that individuals rate their moods, sleep, and daytime functioning at least as favorably as during the baseline period of their normal caffeine consumption. Further studies including randomized placebo control trials using objective measures of sleep and performance are required to confirm these initial pilot findings. Kristen Johannson who carried out this study as part of her Psychology Honours degree.