Why does caffeine sometimes cause energy crashes?
Written by
David Nelson
Reviewed by
Prof. William Dalton, Ph.D.Caffeine causes energy crashes through various physiological processes. It temporarily blocks adenosine receptors to hide the signal of fatigue. So, once the caffeine wears off, adenosine saturates the receptors, leading to a rebound state of extreme exhaustion. I would experience this every day as a barista, but didn't understand why for a while.
Adenosine Rebound
- Caffeine blocks adenosine receptors for 4-6 hours
- Accumulated adenosine causes sudden fatigue when blocking stops
- This rebound effect worsens with frequent high-dose consumption
Blood Sugar Instability
- Caffeine stimulates cortisol release raising blood glucose
- Subsequent insulin surge creates reactive hypoglycemia
- This crash mimics low energy despite adequate calorie intake
Dehydration Effect
- Caffeine acts as mild diuretic increasing fluid loss
- 2% dehydration reduces cognitive performance significantly
- Many forget to compensate with extra water intake
Sleep Disruption
- Afternoon caffeine remains active at bedtime
- Reduces deep sleep stages essential for restoration
- Creates exhaustion cycle even with adequate sleep duration
Strategically manage caffeine times to avoid crashes altogether. It's best to avoid consuming caffeine after 2 PM, given that caffeine has a 6-hour half-life. If you exceed a daily caffeine intake of 200 mg, try to taper off slowly. I switched my afternoon coffee to roasted dandelion root tea and never crashed at 4 PM again.
To offset the effects of caffeine, hydrate and consume protein. For every ounce of coffee, drink an extra glass of water. When using caffeine, opt for protein-dense snacks rather than sugary baked goods. These behaviors will help minimize blood sugar fluctuations and dehydration. My energy level evened out after doing both.
Discover personal caffeine sensitivity by experimenting. Genetic factors significantly impact our ability to metabolize caffeine. To find your baseline, track your feelings and energy levels for three days without consuming any caffeine. This represents how you naturally move through the day. I found out I was administering half the amount needed to obtain the optimum dose.
Read the full article: 10 Natural Ways How Increase Energy
