Researchers at Wageningen University in The Netherlands have linked coffee consumption of over five cups a day to increases in blood pressure, potentially putting you at risk for hypertension and stroke.

That increased heart rate after a few cups of coffee isn't the only change your Starbucks fix could be having on your cardiovascular health. Caffeine has been known to trigger heart palpitations, meaning that a second cup of cold brew could be the reason behind a sudden flutter in your chest. When your heart races, say, in the presence of your crush, that's not a bad thing, but when it's a daily feeling, it could be the result of your coffee habit. Over time, this can lead to iron deficiency, or even anemia, if left untreated. 'Coffee inhibits the absorption of iron,' says Hundt. If you're feeling weak, suddenly bruising easily, or find yourself more lethargic than normal, your coffee habit could be to blame. With that in mind, we've rounded up 20 subtle signs you're drinking too much coffee, from the mildly concerning to the seriously dangerous.

'The effects of caffeine are individualized, so it's best to assess on a case-by-case basis where exactly the tipping point is where caffeine may provide beneficial effects and where it creates diminishing returns,' says Ariane Hundt, MS, a New York-based clinical nutrition coach and fitness expert, who suggests that those who are experiencing more than just alertness from their usual cup of joe might be overdoing it.

Effects of too much caffeine