Not everyone perceives sensations in the same way.
We’re not referring to this in a poetic or spiritual sense. Scientifically, biologically, and literally, people perceive sensations and senses in different ways.
One of the groups of people who experience this are supertasters.
What is a supertaster? Supertasters are those people who have a higher sensitivity to certain tastes, or in general, compared to the average population.
The TAS2R38 gene and supertasters
It all started with phenylthiocarbamide, PTC. This organic compound had a peculiar characteristic: it could taste very bitter or not be perceived at all, depending on the genetic makeup of the person testing it.
When a group of people gathered in 1931 to taste the compound, 65% found it bitter, 28% tasteless, and the remaining 6% described it as having other flavors.
Later studies confirmed that this trait was hereditary, following Mendelian inheritance, meaning the cause was genetic. The heritability of this trait is approximately 70%.
The gene responsible for this phenomenon was discovered in 2003, the TAS2R38 gene. Some have even called it the “supertaster gene.” This gene has two common alleles and five rare variants.
Depending on the genetic sequence of this gene, the protein it codes for, a receptor, has slight differences. These differences make the protein bind to PTC with different intensities.
Since each person has two alleles for this gene, they will have two receptors (which can be the same or different) for PTC.
The combination of all these possibilities creates the different capacities humans have for recognizing PTC when it is introduced into the mouth. It is considered that 85% of a person’s ability to detect the bitter taste comes from this single gene. It is the most important known gene in bitter taste perception.
Although PTC is not a compound found in nature, the same cannot be said for many bitter-tasting toxins. The ability to recognize this taste has been a useful trait throughout history to avoid potential poisons.
Recognizing bitter taste is a defense mechanism to prevent poisoning. The perception of sweet taste also has a biological utility. Sweet foods usually have a high energy value.
Today, it’s not as relevant, but thousands of years ago, every calorie mattered.
Fun fact: the heritability of sweet taste perception is thought to be only about 30%.
Therefore, evolutionarily, the ability to perceive bitter taste was more necessary than perceiving sweetness.
It was used as a genetic test to determine if a person was a supertaster, based on whether they could detect the bitter taste in small amounts of PTC. We could call it a supertaster test. A way to know if you are a supertaster.
Today, it has been replaced by 6-n-propylthiouracil, PROP, a related compound, for safety reasons. This compound is detected by the same gene as PTC.
Filter papers impregnated with PROP are used. The person places it on their tongue and rates it from 1 to 9, from less to more bitter.
Another simpler method is using grapefruits. As absurd as it sounds, it has been shown that there is a correlation between this fruit and the different alleles of the TAS2R38 gene. People who like grapefruit tend to have a low ability to perceive bitter taste.
Research findings suggest that 25% of the population are non-tasters, 50% are medium tasters, and 25% are supertasters.
Taste buds and their role in flavors
However, this gene alone is not enough to explain supertasters. We’re talking about recognizing bitter taste, while a supertaster works with multiple tastes, and involves the sense of smell.
Scientific studies focused on taste perception have shown that alterations in the central nervous system, such as brain lesions, can modify the intensity of tastes in an individual.
It is true that the alleles of this gene have been correlated with aspects of behavior. Those with the most efficient form of the receptor tend to avoid tobacco and alcohol, and have a preference for sweet and chocolate.
Another key point to identify a supertaster is the fungiform papillae.
The fungiform papillae are small bumps where taste buds are located. They are mainly found on the tip and sides of the tongue.
normal person has between 200 and 400 fungiform papillae.
Supertasters are believed to have a higher concentration of fungiform papillae on the tongue compared to the general population. The number of papillae would be:
- 35 papillae per cm² in supertasters.
- 55 papillae per cm² in normal individuals.
- 78 papillae per cm² in individuals with reduced taste perception.
Each taste bud has between 50 and 150 taste receptors.
These receptors are not eternal. Taste cells die and are constantly replaced in these areas of the tongue, with an average lifespan of 10 to 30 days.
As we age, the number of taste receptors decreases.
In theory, a person’s supertaster status could be confirmed with a simple tongue stain using blue food dye and a count of the papillae on a defined surface.
However, some recent studies disprove the relationship between the number of fungiform papillae and being a supertaster.
Being a supertaster
Not everything is an advantage for a supertaster. Due to their heightened sensitivity (and aversion) to bitter taste, they try to mask it with other flavors in their food. For this reason, their salt consumption is higher than in others.
Excess salt in exchange for avoiding alcohol and tobacco. Whether the exchange of products is worth it or not, we leave that to each reader’s discretion.
Additionally, many vegetables taste bitter to them, so they tend to avoid them. It’s not common for a supertaster to enjoy Brussels sprouts.
Again, in another flavor exchange, they avoid very greasy or sweet foods due to the intensity of the taste.
Fun fact: There are more female supertasters than males. It also seems that the number of supertasters is higher in Asian and African populations compared to other ethnicities.
Curious to discover if you are a supertaster? With the tellmeGen DNA test, you can learn about your TAS2R38 gene without having to count the papillae on your tongue.
