When you suddenly stop, you may experience:
Headaches
Fatigue
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
People with anxiety disorders or those who metabolize caffeine slowly may be especially sensitive.
4. Digestive Effects
Coffee stimulates stomach acid production and colon activity.
For some people this can cause:
Acid reflux
Heartburn
An urgent need to use the bathroom
This digestive effect is actually very common and normal.
