The Biology of Coffee -- One of The World’s Most Popular Drinks

The Biology of Coffee -- One of The World’s Most Popular Drinks
From drip coffee to pourovers to stovetop espresso, the variations in coffee-based drinks are plenty.
(Shutterstock)

You’re reading this with a cup of coffee in your hand, aren’t you? Coffee is the most popular drink in many parts of the world. Americans drink more coffee than soda, juice and tea — combined.

How popular is coffee? When news first broke that Prince Harry and Meghan were considering Canada as their new home, Canadian coffee giant Tim Hortons offered free coffee for life as an extra enticement.

Given coffee’s popularity, it’s surprising how much confusion surrounds how this hot, dark, nectar of the gods affects our biology.

Coffee’s ingredients

The main biologically active ingredients in coffee are caffeine (a stimulant) and a suite of antioxidants. What do we know about how caffeine and antioxidants affect our bodies? The fundamentals are pretty simple, but the devil is in the details and the speculation around how coffee could either help or harm us runs a bit wild.

The stimulant properties of caffeine mean that you can count on a cup of coffee to wake you up. In fact, coffee, or at least the caffeine it contains, is the most commonly used psychoactive drug in the world. It seems to work as a stimulant, at least in part, by blocking adenosine, which promotes sleep, from binding to its receptor.

Caffeine and adenosine have similar ring structures. Caffeine acts as a molecular mimic, filling and blocking the adenosine receptor, preventing the body’s natural ability to be able a rest when it’s tired.


 Get The Latest By Email

First name:E-mail:
 


This blocking is also the reason why too much coffee can leave you feeling jittery or sleepless. You can only postpone fatigue for so long before the body’s regulatory systems begin to fail, leading to simple things like the jitters, but also more serious effects like anxiety or insomnia. Complications may be common; a possible link between coffee drinking and insomnia was identified more than 100 years ago.


The National Film Board of Canada produced a documentary on the cultural history of coffee called ‘Black Coffee: Part One, The Irresistible Bean’

Unique responses

Different people respond to caffeine differently. At least some of this variation is from having different forms of that adenosine receptor, the molecule that caffeine binds to and blocks. There are likely other sites of genetic variation as well.

There are individuals who don’t process caffeine and to whom drinks like coffee could pose medical danger. Even away from those extremes, however, there is variation in how we respond to that cup of coffee. And, like much of biology, that variation is a function of environment, our past coffee consumption, genetics and, honestly, just random chance.

We may be interested in coffee because of the oh-so-joyous caffeine buzz, but that doesn’t mean that caffeine is the most biologically interesting aspect of a good cup of coffee.

In one study using rats, caffeine triggered smooth muscle contraction, so it is possible that caffeine directly promotes bowel activity. Other studies, though, have shown that decaffeinated coffee can have as strong an effect on bowel activity as regular coffee, suggesting a more complex mechanism involving some of the other molecules in coffee.

Antioxidant benefits

What about the antioxidants in coffee and the buzz that surrounds them? Things actually start out pretty straightforward. Metabolic processes produce the energy necessary for life, but they also create waste, often in the form of oxidized molecules that can be harmful in themselves or in damaging other molecules.

Antioxidants are a broad group of molecules that can scrub up dangerous waste; all organisms produce antioxidants as part of their metabolic balance. It is unclear if supplementing our diet with additional antioxidants can augment these natural defences, but that hasn’t stopped speculation.

Antioxidants have been linked to almost everything, including premature ejaculation.

Are any of the claims of positive effects substantiated? Surprisingly, the answer is again a resounding maybe.

Coffee and cancer

Coffee won’t cure cancer, but it may help to prevent it and possibly other diseases as well. Part of answering the question of coffee’s connection to cancer lies in asking another: what is cancer? At its simplest, cancer is uncontrolled cell growth, which is fundamentally about regulating when genes are, or are not, actively expressed.

My research group studies gene regulation and I can tell you that even a good cup of coffee, or boost of caffeine, won’t cause genes that are turned off or on at the wrong time to suddenly start playing by the rules.

The antioxidants in coffee may actually have a cancer-fighting effect. Remember that antioxidants fight cellular damage. One type of damage that they may help reduce is mutations to DNA, and cancer is caused by mutations that lead to the misregulation of genes.

Studies have shown that consuming coffee fights cancer in rats. Other studies in humans have shown that coffee consumption is associated with lower rates of some cancers.

Several studies have shown that coffee consumption reduces the rates of some diseases in rats and mice.
Several studies have shown that coffee consumption reduces the rates of some diseases in rats and mice.
(Shutterstock)

Interestingly, coffee consumption has also been linked to reduced rates of other diseases as well. Higher coffee consumption is linked to lower rates of Parkinson’s disease and some other forms of dementia. Strikingly, at least one experimental study in mice and cell culture shows that protection is a function of a combination of caffeine and antioxidants in coffee.

Higher coffee consumption has also been linked to lower rates of Type 2 diabetes. Complexity, combined effects and variation between individuals seems to be the theme across all the diseases.

At the end of the day, where does all this leave us on the biology of coffee? Well, as I tell my students, it’s complicated. But as most reading this already know, coffee will definitely wake you up in the morning.

This is an updated version of a story originally published on Jan. 19, 2020. The original story called coffee the world’s most popular beverage. The term “most popular” can be defined differently. Retail sales of coffee outpace tea globally, but tea is the most consumed beverage after water.

About the AuthorThe Conversation

Thomas Merritt, Professor and Canada Research Chair, Chemistry and Biochemistry, Laurentian University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

More Articles By This Author

You May Also Like

AVAILABLE LANGUAGES

enafarzh-CNzh-TWnltlfifrdehiiditjakomsnofaptruessvtrvi

follow InnerSelf on

facebook-icontwitter-iconrss-icon

 Get The Latest By Email

First name:E-mail:
 

{emailcloak=off}

Marie T. Russell's Daily Inspiration

INNERSELF VOICES

Adapt to the Unexpected with the Overcome Mind-Set
Adapt to the Unexpected with the Overcome Mind-Set
by Jason Redman
Guess what? Life is unfair, and combat is unequivocally unfair. Crazy things happen in combat that…
Reducing the Influence of the Ego... For Our Highest Good
Reducing the Influence of the Ego... For Our Highest Good
by Lawrence Doochin
We each have a choice, and let's be clear what that choice is. Martin Luther King Jr. told us that…
The Healing Power of Imaginative Play
The Healing Power of Imaginative Play
by Carmen Viktoria Gamper
Just as adults benefit from talking about their challenges with friends or a therapist, many…
From Dirt to Soil: Life's Manure Makes For Excellent Growth Potential
From Dirt to Soil: Life's Manure Makes For Excellent Growth Potential
by Alan Cohen
If you or I had met Joe during his risqué comedy stint, we might have judged him as a crude or…
Increasing Healthy Assertiveness and Practicing Assertive Communication
Increasing Healthy Assertiveness and Practicing Assertive Communication
by Tina Gilbertson
Each of us has thoughts, feelings, opinions, preferences, and needs that won’t necessarily jibe…
Horoscope Week: April 5 - 11, 2021
Horoscope Current Week: April 5 - 11, 2021
by Pam Younghans
This weekly astrological journal is based on planetary influences, and offers perspectives and…
10 Reasons Why Men Suffer
10 Reasons Why Men Suffer
by Barry Vissell
I recently finished leading an online men's retreat. Every one of us got deeply vulnerable and,…
Chakra Healing Therapy: Dancing toward the Inner Champion
Chakra Healing Therapy: Dancing toward the Inner Champion
by Glen Park
Flamenco dancing is a delight to watch. A good flamenco dancer exudes an exuberant self-confidence…

MOST READ

The Very Strange History Of The Easter Bunny
The Very Strange History of the Easter Bunny
by Katie Edwards, University of Sheffield
While you’re biting the heads off your chocolate bunnies this weekend, you might wonder how cartoon…
Pluto: Our Inner Darkness Before the Dawn
Pluto: Our Inner Darkness Before the Dawn
by Isabel Hickey
Connecting astrology and mythology, Pluto represents the underworld of the unconscious. It is an…
Believe In Your Genius: Give Yourself a Reputation to Live Up To!
Believe In Your Genius: Give Yourself a Reputation to Live Up To!
by Alan Cohen
Perhaps early in life you adopted a thought about yourself that defined you as small, ugly,…
Are We Entering The Age of the Holy Spirit?
Are We Entering The Age of the Holy Spirit?
by Richard Smoley
The priests of the Age of the Father, whose job centered on sacrifice, would probably not have…
Twin Study Shows Spanking Can Lead To Antisocial Behavior
Twin Study Shows Spanking Can Lead To Antisocial Behavior
by Esther Robards, UT Austin
We found no evidence to support a genetic explanation," says Alexandra Burt. "The differences in…
Why Is The Moon Bright? Your Moon Questions Answered by an Astronomer
Why Is The Moon Bright? Your Moon Questions Answered by an Astronomer
by Jonti Horner, University of Southern Queensland
As someone teaching first-year astronomy at the moment, where much time is spent discussing the…
About Men, Relationships, and the Mind-Body Connection
About Men, Relationships, and the Mind-Body Connection
by Dr. Timothy Johnson
There may be no more important component of personal happiness than your interpersonal…
Covid-19 Spread Is Rare When Schools Use Safe Practices
Covid-19 Spread Is Rare When Schools Use Safe Practices
by Kristina Sauerwein, Washington University
New research finds that, when schools practice mandatory masking, social distancing, and frequent…

New Attitudes - New Possibilities

InnerSelf.comClimateImpactNews.com | InnerPower.net
MightyNatural.com | WholisticPolitics.com
Copyright ©1985 - 2021 InnerSelf Publications. All Rights Reserved.