What makes a supertaster and how to know if you are one

This story was originally published on April 19, 2019.

You've probably noticed that some people can handle — and even enjoy — very bitter things, while others cringe at the mere thought. And while some can't get enough hot sauce, others double over in pain with even mildly spicy dishes.

That's because, like the saying goes, it's all just a matter of taste. And if bitterness and spiciness tend to feel amplified for you, you might be a supertaster — someone who experiences taste more intensely than the average person.

In fact, supertasters can experience more intense taste sensations than others do by about a factor of two, even three, in some cases, according to Linda Bartoshuk, an American psychologist specializing in genetic variations in taste perception. 

Taste is a two-prong reaction, which involves our mouth and throat (taste) as well as our nose (smell), she says.

"Taste — sweet, salty, sour, bitter — for the most part, is hardwired in the brain. We call it hardwired because the newborn baby is born loving sweet and hating bitter."

While tastebuds are located on your tongue, it's only when taste interacts with other senses — like olfaction (smell) and nerve stimulation — that flavour is determined, Bartoshuk says.

"Depending on your experience, your attitude to things like butterscotch and chocolate [flavour] vary. But your attitude toward sweet [taste] doesn't. We all love sweet."

So, what about the person who can't handle spicy or bitter foods? They may just have more tastebuds than the average person, otherwise known as "supertasters," Bartoshuk says.

In the radio special Scrumptious, CBC Radio's science columnist Torah Kachur explores the heightened tastebuds of the supertaster. 

The supertasters

In Bartoshuk's research, she found that 25 per cent of people are incredibly sensitive to a bitter tasting chemical known as 6-n-propylthiouracil, or PROP. Another 25 per cent, deemed non-tasters, can't detect PROP at all, she says, while the remaining 50 per cent are considered average tasters.

While affixing super to anything sounds great, being a supertaster can actually be quite difficult, says Bartoshuk, who coined the terms supertaster and non-taster.

Supertasters are differentially more sensitive to bitter.- Linda Bartoshuk, University of Florida

Having more tastebuds means there are also more pain receptors, and that's why supertasters often can't handle spicy foods and generally avoid anything bitter. As a result, they are often seen as picky eaters.

However, their aversion to bitterness is evolutionary, says Bartoshuk.

"Supertasters are differentially more sensitive to bitter" than the average person.

Bartoshuk says there are 25 different bitter genes expressing 25 different bitter receptors.

"Why would nature do that? Because bitter is our poison detection system." 

So, how do you know if you're a supertaster?

If your reaction to bitterness and spiciness seems to be rather intense, you can confirm whether you're a supertaster with a simple method involving blue food colouring, Bartoshuk says.

Start by swabbing it on your tongue and swallowing a couple of times. Afterwards, you'll notice that those tiny round circles on your tongue, which look a bit like mushrooms, stay pink. Those circles, the fungiform papillae, hold your tastebuds and you can count them with an ordinary magnifying glass.

"The taste buds are actually buried in that tissue and they communicate with the surface of the tongue through a long pore called a taste pore," Bartoshuk said.

If you have more than 30 tastebuds in a space on your tongue that is the size of a hole from a hole punch, you'd be considered a supertaster. The average person has 15 to 30 and those with fewer than 15 would be considered non-tasters.

Those non-tasters may need more spice and flavour to make food taste good.

But your tastebuds and sense of smell won't necessarily always stay the same. Age and a number of ailments can greatly affect these senses.