New York, November 18 (IANS): Are you a tea or coffee person? The answer may result in your genetic predisposition to bitter tastes, the researchers say. It could be because bitterness acts as a natural warning system to protect us from harmful substances. The study, led by researchers at Northwestern University in the US and QIMR Berghofer Medical Research Institute in Australia, investigated reactions to three bitter substances – caffeine, quinine and propyltiouracil (PROP) – to understand how people's preference for drinking tea, coffee and alcohol.
The findings showed that people who were more susceptible to caffeine and drank a lot of coffee consumed small amounts of tea. In other words, people who have an increased ability to taste the bitterness of coffee – and especially the distinctive bitter aroma of caffeine – learn to associate "good things with her".
"You would be expected that people who are particularly sensitive to the bitter taste of caffeine would drink less coffee," said Marilyn Cornelis, assistant professor of preventive medicine at Northwestern University of Medicine School of Medicine. "The opposite results of our study suggest that coffee consumers acquire a taste or the ability to detect caffeine due to the positive gain (stimulation) caused by caffeine." The study, published in the journal Scientific Reports, also found that people sensitive to bitter flavors of quinine and PROP a synthetic taste associated with cruciferous compounds avoids coffee. For alcohol, a greater sensitivity to PROP bitterness resulted in low alcohol consumption, especially red wine.
The findings suggest our perception of bitter taste, informed by our genetics, contributes to preference for coffee, tea and alcohol, Cornelis said. Scientists have applied Mendelian randomization, a technique commonly used in the epidemiology of the disease, to test the causal relationship between bitter taste and beverage consumption in over 4,000 men and women in the UK.