People who drink coffee at least three times a day don’t actually like or enjoy the drink any more than the rest of us, a new study reveals.
German researchers tested both heavy coffee drinkers and low to moderate consumers of the morning mud as part of their investigation into caffeine addiction.
It revealed heavy coffee drinkers had a stronger desire for the beverage without liking or getting more satisfaction from it – classical hallmarks of addiction.
Excessive coffee consumption leads to caffeine addiction in a similar way to other drugs, like cocaine.
It forces the brain to crave the trigger it has become reliant on, but there is no increase in the amount of satisfaction the substance provides.
Coffee drinkers who consume lots of the beverage – at least three cups a day – feel they want to drink it without actually enjoying it
‘These data confirm that heavy coffee consumption is associated with strong wanting despite low liking for coffee, indicating that wanting becomes independent from liking through repeated consumption of caffeine,’ say the researchers, from Friedrich Schiller University Jena in Germany.
‘This dissociation provides a possible explanation for the widespread and stable consumption of caffeine-containing beverages.’
WHAT IS THE IAT?
The implicit association test (IAT) measures the strength of associations between concepts (e.g., black people, gay people) and evaluations (e.g., good, bad) or stereotypes (e.g., athletic, clumsy).
IAT requires subjects to quickly sort words into categories that are on the left and right hand side of the computer screen, using different keys.
IAT measures attitudes and beliefs that people may be unwilling or unable to report.
It may be especially interesting if it reveals an implicit attitude that a subject did not know about.
For example, automatic associations could show a subject associates men with science more than they associate women with science.
IAT has been used in alcohol-related research to demonstrate that heavy alcohol drinkers had stronger associations for alcohol and arousal words compared to alcohol and sedate words.
For this study, researchers used 24 heavy consumers – who drank coffee at least three times a day – and 32 people who either didn’t drink coffee much or didn’t drink it at all.
The frequent coffee drinkers, as expected, showed a higher level of desire for the brown stuff, the team found.
‘Habitual consumers of relatively high levels of coffee (at least three cups a day) differed from low/no coffee drinkers to a much stronger degree in wanting coffee,’ the researchers say in their paper, published in Journal of Psychopharmacology.
The results indicate that heavy coffee drinkers differ from low/non-consumers by displaying increased wanting, but not liking, for coffee.
Researchers say caffeine shares crucial properties with other drugs, such as alcohol or even Class A drugs like cocaine.
‘Dissociations of wanting and liking have been observed with a wide range of drugs in animals,’ they say.
‘The main difference between highly addictive drugs (eg, alcohol or cocaine) and substances with lower addictive strength (eg, caffeine) may mainly be a quantitative rather than a qualitative one.’
For their study, researchers used the implicit association test (IAT), which is usually used to assess unconscious biases relating to race or gender.
IAT, which measures attitudes and beliefs that people may be unwilling or unable to report without unknowingly hiding something, involves pressing computer keys to allocate stimuli into classifications.
The test requires participants to categorise subjects that are individually presented on a computer screen by pressing one of two response keys and evaluate whether they’re ‘good’ or ‘bad’.
It’s thought the difference in reaction times provides a measure of an implicit attitude towards the subject shown on the computer screen.
All participants completed two versions of the IAT, one of which had been developed and validated to assess ‘wanting’ for coffee and the other for ‘liking’.
There was less of a difference between the groups when taking into account IAT results for ‘liking’ coffee, the data revealed.
The study could explain ‘the widespread and stable consumption of caffeine-containing beverages’
Earlier this year, US researchers found environmental differences – notably noise – affect how much perceived flavour there is in a cup of coffee.
In experiments, coffee was perceived as having less aroma by people who were fed loud noise through a pair of headphones while they drank.
Coffee was also more likely to be perceived as expensive and of a higher quality when people were played gentle background noise, as opposed to loud background noise.
Loud noise also had the effect of masking its natural sweetness – meaning it could have the knock-on effect of coffee lovers adding more sugar to their beverage.
The research shows why coffee can often be more pleasurable when drunk in a quiet spot outdoors than in a packed food hall or busy cafe.
‘The results suggest that a loud noise tends to reduce the overall sensitivity of the coffee experience, and this is most clear concerning the bitterness and aroma intensity,’ said the international team of authors in their paper, published in Food Quality and Preference.
BENEFITS OF DRINKING COFFEE
Caffeine has been deemed safe for consumption in doses of up to 400 mg per day for the general population.
Studies suggest it can have a variety of health benefits, including combating liver disease and type two diabetes.
Research has even suggested it could even help people live longer.
It is the world’s most widely consumed stimulant and reports show it can boost daily energy expenditure by around five per cent.
Researchers have said combining two to four daily coffees with regular exercise would be even more effective at keeping the weight off.
A 2015 study showed just a couple of cups a day could help millions of dieters stay trim once they have achieved their desired weight.