No evidence that spice consumption is a cancer prevention mechanism in human populations.

Abstract

Why humans historically began to incorporate spices into their diets is still a matter of unresolved debate. For example, a recent study (Bromham et al. There is little evidence that spicy food in hot countries is an adaptation to reducing infection risk. Nat Hum Behav 2021;5:878-91.) did not support the most popular hypothesis that spice consumption was a practice favoured by selection in certain environments to reduce food poisoning, parasitic infections, and foodborne diseases. Because several spices are known to have anticancer effects, we explored the hypothesis that natural selection and/or cultural evolution may have favoured spice consumption as an adaptive prophylactic response to reduce the burden of cancer pathology. We used linear models to investigate the potential relationship between age-standardized gastrointestinal cancer rates and spice consumption in 36 countries. Patterns of spice are not consistent with a cancer mitigation mechanism: the age-standardized rate of almost all gastrointestinal cancers was not related to spice consumption. Direction other than foodborne pathogens and cancers should be explored to understand the health reasons, if any, why our ancestors developed a taste for spices.