There is nothing like the smell of a fresh brew in the morning. Each sip clears your morning of the haze, getting you strapped up for the day ahead. With over 2.25 billion cups consumed each day, it is one of the most widely enjoyed drinks globally. I personally can’t start my day without one, and I’d bet more than a few of you can’t either. For those who drink it, it is the best drink in the world.
Yes… We are talking about coffee! That enticingly bitter and explosively aromatic bean that is ground and brewed to perfection. For so many of us, it gives us the energy and motivation to start the most arduous of days.
Unfortunately, for those who have certain medical conditions such as high blood pressure, we doctors have recommended a decrease in your caffeine intake. For a long time, doctors have been working on the premise that coffee intake can increase risk factors that lead to heart attacks, strokes and other heart diseases. Interestingly, there has been some significant debate on just how unhealthy coffee is for you, and it may not be as bad as we think.
At a cellular and molecular level, caffeine, a natural chemical found in plants and a component of coffee, affects the heart’s function in many ways. For one, it increases the strength of the heart’s contractions. It can also cause the arteries in the body to constrict.
Due to these effects, coffee theoretically has the potential to increase blood pressure by 10mmHg (units blood pressure is measured in). Doctors and physiologists have also hypothesized that ingesting large amounts of caffeine through coffee could lead to irregular heart rhythms, known as arrhythmias. Arrhythmias come in a variety of forms; some of them are dangerous and some negatively affect long term heart health.
Now, lets get into the details.
Blood Pressure, Heart Disease and Heart Attacks
Problems like high blood pressure and high cholesterol are risk factors for developing heart diseases and having a heart attack. Coffee does have the potential to increase blood pressure due to the effects mentioned above. However, in many of the studies that have been done, it seems that the increases in blood pressure occur in people who don’t drink coffee regularly, and not on the blood pressure in daily drinkers. The increased blood pressure in non-habitual drinkers has the potential to increase their risk for developing heart diseases.
The same does not seem to be true for daily coffee drinkers. More and more studies are beginning to show that there may actually be a benefit to drinking coffee in these people. A large analysis in 2014 (that included over 1.3 million people), and reviewed over 36 other studies, showed that people who consumed around 3.5 cups of coffee per day had a 15% less chance of having a heart attack! For people who drank around 5 cups per day, this risk was the same as the general population. Debates regarding coffee leading to higher cholesterol levels have also been studied, showing that filtered coffee has no effect on increasing cholesterol levels, whereas boiled coffees, like Turkish or Arabic coffee may have an effect on increasing those levels, but the verdict on that is not yet clear.
Strokes
Similarly to heart disease, high blood pressure and cholesterol build up increases your risk of having a stroke. Again, similarly to the findings above, studies on this topic have shown that people with a daily coffee consumption between 1-4 cups actually had less of a chance of developing a stroke than people who did not drink coffee – by around 25%! However, once your consumption increased beyond 6 cups the evidence is unclear.
Arrhythmias
Based on many clinical trials, coffee did not provoke these dangerous heart rhythms in people without preexisting arrhythmias or underlying heart disease. Large studies that looked at people who drank around 3 cups of coffee a day, did not find an association with one of the more common arrhythmias, atrial fibrillation. However, people who have had arrhythmias in the past are still encouraged to avoid coffee. There have been some recorded cases of arrhythmias in people who ingest higher than normal amounts of coffee (around 4-5 cups a day). Keep in mind we are only talking about coffee here, and not energy drinks or other forms of caffeine.
Well, what does this all mean?
So from a heart disease perspective, if you don’t drink coffee on a daily basis, your occasional cup of coffee can actually increase your blood pressure and may increase risk for heart disease. For those daily coffee drinkers, their blood pressures tend to not change with coffee intake. Those who drink around 4 or less cups a day could actually have a lower chance of having both strokes and heart attacks. Moderate coffee intake could potentially trigger dangerous heart rhythms in those who already have risk factors or a history. Those without risk factors could be at risk if coffee is consumed in large amounts.
I think I would be amiss in not mentioning that the effects we are seeing are from the coffee itself, and not the sugar, whipped cream, vanilla or mocha flavorings that are sometimes added to our drinks. To top it off, smoking is also known to be a common habit that people partake in while enjoying a cup of coffee, and we would obviously encourage anyone and everyone who smokes to quit as this is a clear risk factor for heart disease. Again, keep in mind these studies just looked at coffee and not other forms of caffeine. Despite the promising findings we are seeing in these studies for daily drinkers, coffee, like all things, should be enjoyed in moderation, as the potential harmful effects may not have been identified yet or are dependent on your overall health and other medical conditions.
So, as we daily coffee drinkers sip on our americanos, cappuccinos, espressos and lattés, we can take some solace in the fact that this drink we relish may actually benefit our bodies… other than just waking us up in the morning!
Happy sipping!
-Dr. K
