The public and media seem to have a love/hate relationship with coffee. Or, more specifically, with caffeine. Good for you? Bad for you? Neutral? From “it’ll stunt your growth,” to recent findings that it may provide protection against various serious diseases (Alzheimer’s, liver cancer, type 2 diabetes), there’s a lot of buzz surrounding coffee and its most famous constituent, caffeine.
The World’s Favorite Drug
Of course, caffeine is a stimulant, which accounts for its energizing reputation. In fact, according to scientists writing recently in Frontiers in Psychiatry, “caffeine is the most widely consumed psychoactive drug in the world”. But this stimulant effect also accounts for its reputation as a substance that can, in too-high doses, cause the jitters, insomnia, or worse. So what’s the real story? Is caffeine a drug that taxes health, or a welcome natural compound that helps keep people alert when their energy is flagging?
And what, if any, are its effects on the heart and cardiovascular system? Does it raise blood pressure, for instance? And what about caffeine’s notorious diuretic effect? While it’s true that caffeine stimulates urine production, which could be dehydrating, in reality, drinkers who are accustomed to its effects experience a net hydration effect when drinking coffee, not a dehydrating one. That’s because our bodies tend to adapt to the substances we consume regularly. While someone who has never consumed caffeine will experience caffeine’s diuretic effect, regular drinkers needn’t worry about this.
As you might imagine, the answers to these and other health-related questions surrounding coffee and caffeine are nuanced, to say the least.
Caffeine and Blood Pressure
Also present in tea, caffeine is counterbalanced in green tea by a companion molecule; a unique amino acid called theanine. Research indicates that theanine exerts a calming effect, fostering focus and attention, while reducing anxiety. This may account for tea’s reputation as a calming, relaxing beverage that nevertheless promotes concentration and mental alertness.
While you might expect that caffeine consumption is associated with higher blood pressure and potentially greater risks of heart disease, research does not bear this out. In fact, a recent study published in Mayo Clinic Proceedings showed that caffeine consumption—whether coffee was involved or not—is associated with a significant reduction in the risk of all-cause mortality. When you drill down into the data, you discover that caffeine’s effects on the cardiovascular system are essentially neutral. The benefits accrue through protection against a host of other diseases, such as certain types of cancer.
While unaccustomed drinkers may experience some brief elevations in heart rate or blood pressure after consuming caffeine, these effects are fleeting, and reversible. Overall, according to a recent report: “…typical moderate caffeine intake is not associated with increased risks of total cardiovascular disease [including] arrhythmia; heart failure; blood pressure changes among regular coffee drinkers; or hypertension in baseline populations.”
Another recent review of previous studies concluded, “…coffee consumption in moderation is safe and is beneficial in both healthy persons as well as patients with high blood pressure…” Other researchers note coffee’s beneficial effects on other health related conditions. “Coffee was associated with a probable decreased risk of breast, colorectal, colon, endometrial, and prostate cancers; cardiovascular disease and mortality; Parkinson’s disease; and type-2 diabetes,” researchers wrote, in the Annual Review of Nutrition.
Another recent study, published in The Journal of Nutrition, noted that studies that found a protective effect for caffeinated coffee consumption involved subjects who drank four or more cups per day. Indeed, 4-6 cups per day appears to confer significant protection against a wide range of diseases. In general, one cup of brewed coffee contains about 100 mg. caffeine, although precise amounts will vary widely depending on various factors.
However, many studies have concluded that decaffeinated coffee confers health benefits, too, which suggests that some of the hundreds of other compounds in this complex brew are also beneficial. Among these, chlorogenic acid is suspected to be especially healthful.
Whether you choose decaf or regular, coffee is nothing short of a superfood health drink. Far from causing health problems, its regular consumption is linked to reduced risks of a host of diseases and conditions.