Coffee might be your morning love language, but that love can sometimes get a little intense. Your body has ways of telling you when your coffee habit has crossed the line, often through odd quirks. Here are nine signs your caffeine is creeping too high.
9. Frequent Bathroom Trips
If you notice you’re constantly excusing yourself during meetings or long drives, caffeine could be the culprit. It acts as a mild diuretic, making your kidneys release more sodium and water into your urine. The effect is stronger when you drink higher amounts or consume caffeine all at once. This is why a triple espresso might hit your bladder harder than a slow-sipped cup.
8. Digestive Discomfort (Heartburn or Reflux)
That burning in your chest after your second latte isn’t random. Caffeine stimulates stomach acid production and relaxes the lower esophageal sphincter, which is the valve that keeps acid from rising. The result? Heartburn, burping, or even a sour taste in your throat after drinking coffee. If your gut feels unsettled, try not to drink caffeine on an empty stomach or switch to cold brew, which tends to be gentler.
7. Jitters and Shaky Hands
If you’ve ever looked down and noticed your hands trembling after a strong cold brew, that could be a sign of caffeine overload. What’s happening is that caffeine blocks adenosine, a neurotransmitter that signals calmness, while increasing adrenaline, the “fight or flight” hormone. If jitters happen often, try dialing back the size of your drinks.
6. Feeling Anxious or Restless
Caffeine primes your brain to be more alert, which can tip into anxiousness. Studies show high caffeine intake raises cortisol and adrenaline levels, making you feel tense or even panicky if you’re sensitive. A 2024 meta-analysis found that daily doses above roughly 400 mg raised anxiety scores in participants.
5. Heart Racing or Palpitations
A pounding heartbeat can be unsettling, and caffeine is often to blame. It stimulates the release of catecholamines, which are hormones that speed up your heart rate. For sensitive individuals, even moderate amounts can trigger palpitations. If your heart starts racing after coffee, cut back and track your intake.
4. Trouble Sleeping or Staying Asleep
No debate needed: coffee does interfere with sleep. It blocks adenosine, the brain’s natural sleepiness signal, and coffee’s half-life means it can stay active for 5–7 hours. So even coffee in the afternoon may reduce your deep sleep at night. A simple fix is to set a “caffeine cutoff,” and for many people, that’s around 2 p.m.
3. Headaches That Come and Go
Caffeine and headaches have a complicated relationship. In small, occasional doses, coffee can ease migraines because it narrows blood vessels in the brain. But regular heavy use can backfire. When caffeine wears off, those blood vessels dilate again, causing withdrawal headaches. If you’re getting headaches more often, either daily or when you miss your usual cup, your body might be depending on caffeine too much.
2. Tolerance
Remember when one small cup of coffee was enough? If now it takes three or four just to feel “normal,” that’s tolerance kicking in. Your body adapts by creating more adenosine receptors, which means the same dose has less effect over time. The fix isn’t more caffeine but less. Try cycling your use: take two or three “low caffeine days” each week, sticking to tea or half-caf, so your system can reset.
1. The Crash (Wired Then Wiped Out)
This is perhaps the clearest sign you’ve had too much caffeine. You feel unstoppable for a few hours, then suddenly exhausted or cranky. That roller coaster comes from caffeine’s quick boost to dopamine and adrenaline, followed by a quick dip when the effect wears off. To avoid the crash, pair caffeine with healthy habits: eat balanced meals with protein and fiber, hydrate well, and limit coffee to earlier in the day.