It’s two o'clock in the afternoon and you’re beginning to feel that midday slump. You make your way to the coffee machine for the third time since the morning.
But, it doesn’t matter how many cups of coffee you have — your body refuses to stay alert, leaving you with the jitters instead.
Although coffee is known to boost energy levels and help us stay alert, consuming too much of it can also have adverse effects on our body. While it’s common to drink multiple cups a day, it might be affecting your ability to sleep, increasing anxiety levels and causing digestive issues.
Think this might be you? Here are five of the most noticeable health implications of consuming too much coffee or other sources of caffeine.
Anxiety and stress
While it’s perfectly normal to experience anxiety, drinking too much coffee might induce it.
Caffeine blocks the natural brain chemical adenosine which makes our bodies feel tired and increases adrenaline — the “fight or flight” hormone that boosts energy levels. This causes our heart rate to speed up and makes our body think we’re anxious.
Anisa Morava, a second-year PhD student in kinesiology, said that caffeine withdrawal can also exacerbate anxiety.
“Some of the concerns with excessive caffeine consumption include withdrawal symptoms such as headaches, irritability, depressed mood and fatigue, and in some individuals, anxiety or anxiety-like symptoms,” says Morava. “Some individuals are more sensitive to caffeine and it exacerbates feelings of anxiety that they already are experiencing.”
Unsurprisingly, caffeine-induced anxiety disorder is a subclass of the DSM-5 diagnosis of “substance-induced anxiety disorders,” as caffeine is widely known for its stimulant effects of nervousness, restlessness and insomnia.
If you’re someone who struggles with anxiety on a regular basis, consider limiting your coffee intake to one to two cups per day, ideally in the morning.
Trouble sleeping at night
One of coffee’s greatest, and simultaneously worst traits, is its ability to keep us awake.
While a small amount of caffeine may have little to no effect on our body’s ability to snooze, drinking too much can increase the time it takes our bodies to fall asleep at night. Even drinking coffee in the middle of the day could be affecting your nighttime sleep — depending on your genetics, caffeine can stay in your system anywhere from one and a half to nine hours.
Coffee also affects the length of your sleep and its quality, which might explain why you don't feel refreshed waking up in the morning, even after a full night of sleep. Drinking too much can also worsen pre-existing insomnia symptoms, such as nighttime anxiety and recurrent awakenings mid-sleep.
Instead of having a cup of coffee midday to boost your energy levels, it might be beneficial to go for a 20-minute brisk walk instead.
Increased blood pressure
Coffee increases your blood pressure shortly after you drink it because of its effect on the nervous system.
Caffeine causes a short, dramatic spike in blood pressure levels shortly after consumption, but this is more common in people who consume coffee infrequently. Luckily, caffeine has not been linked to heart disease, strokes or high blood pressure over a prolonged period of time. However, drinking more than six cups of coffee a day could heighten the risk of cardiovascular disease.
Stomach and digestive issues
Ever noticed that a cup of coffee makes you need to run to the bathroom?
That’s because drinking coffee releases gastrin — a peptide hormone that stimulates the release of gastric acid into your body — accelerating movement in your colon.
Gastric acid, better known as “stomach acid,” is a digestive fluid that is produced within the lining of your stomach. Having too much stomach acid in your system can cause abdominal pain, bloating, nausea, diarrhea and decreased appetite. In turn, these effects cause discomfort and more frequent trips to the bathroom.
If you’ve ever experienced a “caffeine crash” then you know it’s because of caffeine-induced fatigue.
While it’s normal to feel sluggish after consuming coffee, opting for more when you feel tired can have negative effects on your sleep. Remember that other fluids such as tea, pop and energy drinks also contain caffeine, so they might not be the best alternative.
Morava conducted a study in collaboration with Western University's Exercise and Health Psychology Laboratory director Harry Prapavessis and found that a walk as short as 20 minutes can have the same effect as a cup of coffee on energy levels and working memory.
“We tested individuals in the study with a 20-minute bout of acute aerobic exercise, which was basically walking on a treadmill at a brisk pace and comparing that to the equivalent of one cup of coffee,” says Morava. “We found that when regular caffeine consumers did the exercise, they pretty much had the same working memory effects as they did with a cup of coffee. We found similar results in non-caffeine drinkers as well.”
“Exercise improves your mood, it improves your energy levels, it improves cognitive functioning,” mentions Morava. “If you need to do work but feel tired, what you can do is kind of go for a 20-minute brisk walk before you do that task. And you may feel that you have more energy or that you're more focused.”
Alternatively, eating whole foods with a low glycemic index — meaning their natural sugar is absorbed slower than foods with refined sugars — is a much healthier way to boost your energy levels. In other words, their natural, slow digestion process may help you feel more alert for longer periods of time. Foods with a low glycemic index include high fibre foods such as apples, almonds, whole grain bread and legumes, including others.
So the next time you start to feel that midday crash, consider grabbing a high fibre snack or going for a short walk to help you re-energize. You’ll avoid the coffee jitters and, chances are, you’ll feel more alert than with another cup of coffee.