Taste shaped the use of botanical drugs

The perception of taste (here defined as a combination of taste, odour and chemesthesis) enables animals to find high-value foods and avoid toxins. Humans have learned to use unpalatable and toxic substances as medicines, yet the importance of taste perception in this process is poorly understood. Here we generate tasting-panel data for botanical drugs and apply phylogenetic generalised linear mixed models to test whether taste intensity, complexity and particular tastes can predict ancient Graeco-Roman drug use. We found taste to be strongly predictive of therapeutic use: botanical drugs with high therapeutic versatility have simple yet intense tastes, and 21 of 22 tastes predicted at least one therapeutic use. In addition to the common notion of bitter tasting medicines, we also found starchy, musky, sweet, cooling, and soapy tasting drugs associated with versatility. In ancient Greece and Rome, illness was thought to arise from imbalance in bodily fluids or humours, yet our study suggests that uses of drugs were based on observed physiological effects that are often consistent with modern understanding of taste receptor pharmacology and medicine.