When you are cleaning your fridge and you find leftovers, you make sure to check if they are still edible. To do so, you smell them, look out for unusual texture or color and sometimes taste a little bit. Using these techniques, most of us can tell which food is no longer safe to eat.
These are some skills that are the result of evolution. Human beings are only able to tell which substances are poisonous and should be away from us only because of these sharps senses and abilities.
Sharp, repugnant smells and tastes are often an indication of toxic substances. Most of us will deduce that whatever plant or food we are near contains something poisonous. This is actually true and such smells or tastes can be because of the presence of harmful alkaloids.
However, scientists have been confused one particular beverage that tastes bitter but is extremely popular among the masses – coffee. You probably know someone who cannot survive a day without coffee throughout the day.
But why is this so? If humans have evolved to stay away from bitterness and unpleasant tastes, why is there a huge population of coffee consumers around the globe? In theory, people are supposed to stay away from the drink but the reality is quite opposite.
New research may answer this fascinating question about coffee. It puts forward a theory on the link between genetic sensitivity to bitter substances, and the average amount of bitter foods consumed.
The study was conducted by researchers from Northwestern University Feinberg School of Medicine in Chicago, IL, and QIMR Berghofer Medical Research Institute in Australia. It is published in the journal Scientific Reports.
Read the study here.
How Was the Study Conducted?
According to Marilyn Cornelis, assistant professor of preventive medicine at Northwestern University, even though scientists know a lot about taste today, the mechanics behind it are still not clear.
The new study uses two different datasets. The first one is data on Australian twins which shows links between genetic variants and taste development. The second dataset comes from the UK Biobank. From the latter, the researchers looked at samples of around 400,000 people along with questions on beverage consumption.
Taking the data sets, the researchers then examined genetic variants and the consumption of coffee using Mendelian randomization.
After examining, the team found the people who were more sensitive to bitterness in the beverages consumed a higher quantity of coffee. This is the opposite of what most people expect. You may have also thought that people who are more sensitive to bitterness are less likely to have it. So, what is the explanation for this?
The researchers have the answer to that question. The effects of caffeine are well-known. Drinking coffee can help stimulate the brain and lead to better concentration and work performance.
According to the researchers, these effects act as positive reinforcement. The people who consume coffee on a daily basis can acquire a taste for it or become more sensitive to caffeine.
What Are the Future Prospects?
The researchers agree that the study has some limitations. Further research is required to learn more about the relationship between taste developments and genetics. In addition, studies are also needed to see whether non-European people have the same effects.
For now, the study does make the reasoning for why people cannot stop drinking coffee and caffeine-rich beverages even if they are harmful clear.