Joshua Kistler

This study shows that regular daytime caffeine intake in men reduces REM sleep promotion and worsens sleep quality compared to placebo.

This study investigates the impact of daily caffeine intake on nighttime sleep in habitual consumers, finding no significant differences in sleep structure or quality but reduced sigma frequency EEG power density, suggesting early signs of overnight withdrawal.

This study examines how daily caffeine intake and withdrawal affect circadian rhythms and wakefulness in habitual consumers, finding no significant changes in melatonin or cortisol but increased sleepiness and attentional lapses during withdrawal.