Whether you like coffee and beer is in the genes , but it's the buzz that makes us like them, not the taste.
Mutations that cause different reactions to the stimulating beverages have been identified for the first time.
It means our choices depend on how the pick me ups make us feel – rather than the taste, say scientists.
The breakthrough could lead to a fresh approach in combating obesity and alcohol abuse.
It also sheds light on why some of us can gulp down a cup of coffee before bed and sleep peacefully and others cannot.
The first genome wide test for bitter and sweet drinks showed preferences hinge on their effects on the brain instead of the taste buds.
Dr Marilyn Cornelis and colleagues mapped the complete DNA of 336,000 individuals from the UK Biobank, a long running survey following the health of around half a million Britons.
To their surprise a greater liking for coffee, alcohol or sweet beverages was not based on taste gene variants – but those related to the "psychoactive" properties.
These are the chemicals, such as caffeine in coffee and carbonated drinks for instance, that act upon the central nervous system.
This alters brain function – resulting in temporary changes in perception, mood, consciousness and behaviour.
Dr Cornelis, assistant professor of preventive medicine at Northwestern University, Chicago, said: "The genetics underlying our preferences are related to the psychoactive components of these drinks.
"People like the way coffee and alcohol make them feel. That is why they drink it. It is not the taste."
It explains why you may swig ale or a glass of wine – while a colleague may ask for a hot brew or a can of cola.
Understanding the phenomenon offers hope of intervening in people's diets, said Dr Cornelis.
The study published in Human Molecular Genetics highlights the important "behaviour-reward" components to beverage choice.
It adds to knowledge about the connection between genetics and beverage consumption – and the potential barriers to changing it.
Sugary beverages are linked to a host of disease and health conditions. Alcohol intake is related to more than 200 diseases, accounting for about six percent of deaths globally.
On the other hand, there is a growing body of evidence that regular cups of coffee can stave off dementia, heart disease and other illnesses.
Interestingly, one specific mutation fuelled an urge for fizzy drinks. The variant of the gene called FTO gene has previously been associated with a lower risk of obesity.
Dr Cornelis said: "It is counter intuitive. FTO has been something of a mystery gene, and we don't know exactly how it is linked to obesity. It likely plays a role in behaviour, which would be linked to weight management."
In the study, beverages were categorised into bitter and sweet tasting groups. The former included coffee, tea, grapefruit juice, beer, red wine and liquor.
The latter were sugar and artificially sweetened beverages such as energy and fizzy drinks respectively, and other fruit juices.
Intake was collected using 24-hour dietary recalls or questionnaires and the team counted the number of servings consumed by the participants.
Then they did a genome-wide association study of bitter and sweet beverage consumption, before confirming the key findings in three US cohorts.
First author Victor Zhong, a postdoctoral fellow in Dr Cornelis' lab, added: "To our knowledge, this is the first genome wide association study of beverage consumption based on taste perspective.
"It is also the most comprehensive genome-wide association study of beverage consumption to date."
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