It’s true, science tells us. And it’s also a nutty, counter-intuitive notion that we humans should enjoy drinking such a bitter, astringent brew. Bitterness perception is a natural warning system to protect us from harmful substances, so we really shouldn’t like coffee…
Happy Coffee drinkers: Note the telltale pinpoint pupils and
piercing stares of these heavily-addicted imbibers…
…But we do, and how! So why do we love Coffee enough to support a dedicated production and processing industry, a major ‘department’ in every supermarket, a huge market for Coffee makers and other accoutrements, and several chains of restaurants with thousands of outlets around the world that cater primarily to Coffee service?
What they did…
For the study, scientists applied Mendelian randomization, a technique commonly used in disease epidemiology, to test the causal relationship between bitter taste and beverage consumption in more than 400,000 men and women in the United Kingdom. The genetic variants linked to caffeine, quinine and phenylthiocarbamide (PROP) perception were previously identified through genome-wide analysis of solution taste-ratings collected from Australian twins. These genetic variants were then tested for associations with self-reported consumption of Coffee, Tea and Alcohol, respectively, in the current study.
What they found…
Study participants who were more sensitive to caffeine and were drinking a lot of coffee consumed low amounts of Tea. But that could just be because they were too busy drinking Coffee, notes Dr. Marilyn Cornelis, Assistant Professor of Preventive Medicine at Northwestern University’s Feinberg School of Medicine, and Lead Author of the report.
The study also found people sensitive to the bitter flavors of quinine and of PROP, a synthetic taste related to the compounds in Cruciferous Vegetables, avoided Coffee. For Alcohol, a higher sensitivity to the bitterness of PROP resulted in lower Alcohol consumption, particularly of Red Wine.
The takeaway…
“You’d expect that people who are particularly sensitive to the bitter taste of caffeine would drink less Coffee,” Cornelis says. “The opposite results of our study suggest coffee consumers acquire a taste or an ability to detect caffeine due to the learned positive reinforcement (i.e. stimulation) elicited by caffeine.”
In other words, people who have a heightened ability to taste coffee’s bitterness – and particularly the distinct bitter flavor of caffeine — learn to associate ‘good things with it’.
My take…
Nobody I know started drinking Coffee because they were attracted to the flavour or aroma. They started because Coffee was a relatively cheap and harmless way to get an ‘energy boost’, and they used Cream and or Sugar, at least at first, to mask the bitterness and astringency. After one is addicted to caffeine, they’ll put up with the unpleasant aspects of Coffee’s flavour to get their hit. Simple as that. I worked in radio news when I broke into journalism. One of my rites of passage in the business was working the all-night shift in the Newsroom, and there I acquired an extremely heavy Coffee habit. When my doctor suggested I cut down, I elected to start drinking my Coffee black, thereby reducing its attractiveness. And I did cut down, drastically.
So, talk genetics all you like, and theorize to the limits of your curiosity about relative sensitivities to various bitter compounds. It’s the caffeine high that makes us drink Coffee as aggressively as we do.
Dr. Obvious contributed to this report.
~ Maggie J.