Quirks and Quarks

How come I can't tolerate spicy foods, but my kids can?

It comes down to how many heat receptors are in your mouth, which comes down to genetics.

It comes down to how many heat receptors are in your mouth.

A competitor taking part in a chilli pepper eating contest in a hot spring filled with chilli peppers. (STR/AFP via Getty Images)

Today's question comes from Anita Mark in Victoria, British Columbia. She asks:  

Why does my mouth burn when I eat hot, peppery, or spicy foods, when many other people, including my kids, have no problem with them?

Paul Bosland, the director of the Chile Pepper Institute at New Mexico State University explains that it depends on how many heat receptors you have in your mouth. The more heat receptors you have, the more sensitive you are to chili pepper heat.

Capsaicinoids —  the alkaloids that give peppers their spice — attach to the same receptors that detect heat, like a cup of hot tea. The reason some people can eat really spicy foods is that they do not have as many heat receptors in their mouth. The more heat receptors you have, the more sensitive you are to those capsaicinoids.

The number of receptors is based on genetics. You can build up a tolerance over time but unfortunately if you quit eating chili that tolerance seems to go away and you have to start all over again.