Approved research

Estimating causal links between habitual caffeine consumption and objective measures of sleep quality in the general population.

Lay summary

Because of its stimulating and wake-promoting properties, caffeine is the most widely consumed psychoactive substance in the world. Laboratory studies demonstrate that an acute, single dose of caffeine negatively affects the quality and depth of sleep. Nevertheless, most people consume caffeine contained in drinks and foods on a daily basis and over prolonged periods of time. It is currently unknown whether such intake also has a negative impact on sleep. This question will be addressed in this study. The question is important because good quality sleep is essential for good quality of life and personal health. Thus, deep and undisturbed sleep contributes to consolidation of memories, restoration of brain functions, resistance against infections, removal of waste products from brain and body, and has many other beneficial effects on the entire organism. It is expected that the project will last approximately 12 months, during which the above mentioned questions will be investigated on the bases of two large and representative community samples.