Effects of caffeine on sleep quality and daytime functioning

This review evaluates the effects of caffeine on sleep quality and daytime functioning. Caffeine disrupts sleep by reducing melatonin levels, shortening total sleep time, and delaying deep sleep phases. While caffeine improves alertness and cognitive performance during the day, these benefits are often a reversal of withdrawal effects, rather than a net gain. Long-term use can lead to tolerance, requiring higher doses for the same effect, which worsens sleep disruption. The findings highlight caffeine's dual role as a performance enhancer and a sleep disruptor, underscoring the need for balanced use to protect brain health and cognitive recovery.

Limit caffeine consumption, especially in the afternoon and evening, to preserve sleep quality. Consider gradually reducing daily caffeine intake to prevent withdrawal effects and improve natural alertness. These recommendations are based on robust evidence linking caffeine to both enhanced daytime functioning and disrupted nighttime sleep. Individual responses vary, so personalized strategies may be needed for optimal balance.