New York, November 18 (IANS): Are you a tea or coffee? The answer might lie in your genetic predisposition to bitter taste, the researchers said. It could be because bitterness acts as a natural warning system to protect us from harmful substances. The study, led by researchers from Northwestern University based in the US, and QIMR Berghofer Medical Research Institute in Australia, explored reactions to three bitter substances – caffeine, quinine and propylthiouracil (PROP) – to understand how they influence people's preferences for tea, coffee and alcohol.
The findings show that people who are more sensitive to caffeine and drink lots of coffee consume low amounts of tea. In other words, people who have a high ability to feel the bitterness of coffee – and especially the different bitter taste of caffeine – learn to connect "good things with it".
"You hope that people who are very sensitive to the bitter taste of caffeine will drink less coffee," said Marilyn Cornelis, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine. "Opposing results from our study show coffee consumers gain a sense or ability to detect caffeine because of the positive reinforcement of learning (stimulation) caused by caffeine." The study, published in the journal Scientific Reports, also found that people were sensitive to the quinine and PROP bitter Synthetic flavors associated with compounds in cruciferous vegetables avoid coffee. For alcohol, a higher sensitivity to PROP bitterness results in lower alcohol consumption, especially red wine.
"These findings indicate our perception of bitter taste, which is informed by our genetics, contributes to the preference for coffee, tea and alcohol," Cornelis said. Scientists apply randomization of Mendel, a technique commonly used in epidemiology of disease, to test the causal relationship between bitter taste and drink consumption in more than 4,00,000 men and women in the UK.