Improved Attention and Reaction Time: Caffeine blocks adenosine receptors in the brain, which prevents drowsiness and increases alertness. Caffeine enhances attention, vigilance, and reaction time, making it beneficial for both cognitive performance and mood. (1, 2)
Mood Enhancement: Regular caffeine consumption has been shown to boost mood by increasing feelings of well-being and reducing fatigue. This is due to its stimulating effect on the central nervous system, which can help alleviate feelings of depression and anxiety (10, 11, 12)
Physical Performance
Enhanced Endurance and Strength: Caffeine can significantly improve physical performance by increasing adrenaline levels and releasing fatty acids from fat tissues, which muscles then use for energy. Ganio et al. (2009) discussed the evidence of caffeine supplementation improving cycling endurance, making it a valuable ergogenic aid for athletes. (3)
Exercise Performance and Fatigue Reduction: Caffeine can enhance exercise performance by reducing perceived exertion and fatigue. This allows athletes to train harder and for longer periods. (6)
Brain Function and Neuroprotection
Reduced Risk of Neurodegenerative Diseases: Long-term caffeine consumption has been associated with a lower risk of developing neurodegenerative diseases like Parkinson’s and Alzheimer’s. Regular moderate caffeine intake was linked to a reduced risk of Parkinson's disease. (7) Similarly, Eskelinen et al. (2009) reported that midlife coffee drinking correlated with a lower risk of dementia and Alzheimer's later in life. (4,5)
Antioxidant Properties: The antioxidants in caffeine help reduce oxidative stress and inflammation, protecting brain cells and supporting overall brain health. (8, 9)
Metabolism
Resting Metabolic Rate (RMR): Caffeine has been shown to increase the resting metabolic rate (RMR) by up to 12%, which is the number of calories the body burns while at rest. (13) A higher RMR means the body uses more energy, which can contribute to weight loss or maintenance. Another study also showed similar results where caffeine increased energy expenditure significantly up to 300%, in a dose dependent manner (14)
Fat Oxidation: Caffeine stimulates the central nervous system, leading to the release of adrenaline, which promotes the breakdown of fat cells, releasing fatty acids into the bloodstream to be used as fuel, thereby enhancing fat oxidation. Research suggests that caffeine intake before exercise increases the rate of fat oxidation during the activity (15), and that caffeine increases fat oxidation by 10-29% in both lean and obese individuals (16)
References
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Ganio, M. S., Klau, J. F., Casa, D. J., Armstrong, L. E., & Maresh, C. M. (2009). Effect of caffeine on sport-specific endurance performance: a systematic review. Journal of strength and conditioning research, 23(1), 315–324. https://doi.org/10.1519/JSC.0b013e31818b979a
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