Key Takeaway
Comprehensive review showing caffeine improves alertness, attention, reaction time, and cognitive performance, particularly when fatigued or sleep-deprived.
Summary
This extensive review examined caffeine's effects on cognitive function, physical performance, and occupational performance. It included evidence from military, workplace, and sports contexts.
The review found robust evidence that caffeine improves vigilance, alertness, attention, and reaction time. Effects were largest when individuals were fatigued or sleep-deprived. Moderate doses (200-400mg) were optimal for cognitive benefits.
The paper also addressed practical applications for shift workers, military personnel, and athletes.
Methods
- Comprehensive narrative review
- Included military and occupational studies
- Examined dose-response relationships
- Assessed effects on various cognitive domains
Key Results
- Improves vigilance and alertness
- Enhances reaction time by 5-10%
- Benefits attention and concentration
- Effects largest when fatigued
- Moderate doses (200-400mg) optimal for cognition
Limitations
- Tolerance effects with chronic use
- Individual genetic variation affects response
- Most studies on acute dosing
- Sleep disruption with late dosing