Expert: Dana Krempels, Ph.D. - 10/25/2008

Question
I learned recently that there are natural chemicals in foods that effect whether organisms want to eat the food or not. Like some toxic chemicals in leaves keep bugs from eating them. So, I was wondering what kind of chemicals are there in foods like broccoli and celery that makes me not want to eat them?

Answer
Dear Erika,

Wow, that's a great question!  

Many people have different "taste" when it comes to foods, and it may be that you are more sensitive to the strong-smelling and tasting sulfur compounds that the brassicaceous vegetables such as broccoli and cabbage have in their tissues.  

Cultivated varieties of Brassica oleracea (the wild species that has been selected to become broccoli, cauliflower, cabbage, Brussel's sprouts, rabe, rappini, kholrabi, etc.) have far less of these noxious compound in them than the wild versions, and the wild versions have even more compounds--such as isothiocyanates and other compounds designed to deter insect herbivores.  But the domestic varieties still have traces of these, and it's possible that people who don't like broccoli and it's cousins are simply more sensitive to the taste of these trace compounds than other people.

Or maybe that the people who *like* broccoli actually enjoy the weird taste of those trace amounts of chemicals, too little to hurt them, but still enough to taste.

Hope that helps.

Dana