Irritability
Difficulty concentrating
While this isn’t considered a true addiction, it is a real physical dependence.
2. Sleep Disruption
Caffeine has a half-life of about 5–6 hours.
That means if you drink coffee at 8 a.m., about 25% of the caffeine may still be in your system by 8 p.m.
Even if you fall asleep easily, caffeine can:
Reduce deep sleep quality
Make sleep less restorative
3. Anxiety and Jitters
Consuming too much caffeine—typically more than 400 mg per day (about four cups)—can lead to:
Rapid heartbeat
Nervousness
Tremors
Anxiety
