Herbs and spices are commonly consumed in different regions for culinary and medical purposes. Herbs and spices may have several positive health effects due to their phytochemical contents that have already been discussed in several studies. In this study, the main aim was to review and discuss the possible toxic effects of commonly used herbs and spices. The dose-dependent toxic effects of herbs and spices are important to create public awareness on the consumption of these phytochemical sources for both culinary and medical purposes. Even though the health-promoting effects of these herbs and spices at lower concentrations have been reported in various studies, each herb and spice may become toxic after a certain dose. In addition to the general evaluation of these herbs and spices, susceptible organs or systems in living organisms were presented in this chapter covering several in vivo studies.
