The importance of the olfactory system in human well-being, through nutrition and social behavior

The human sense of smell is still much underappreciated, despite its importance for vital functions such as warning and protection from environmental hazards, eating behavior and nutrition, and social communication. We here approach olfaction as a sense of well-being and review the available literature on how the sense of smell contributes to building and maintaining well-being through supporting nutrition and social relationships. Humans seem to be able to extract nutritional information from olfactory food cues, which can trigger specific appetite and direct food choice, but may not always impact actual intake behavior. Beyond food enjoyment, as part of quality of life, smell has the ability to transfer and regulate emotional conditions, and thus impacts social relationships, at various stages across life (e.g., prenatal and postnatal, during puberty, for partner selection and in sickness). A better understanding of how olfactory information is processed and employed for these functions so vital for well-being may be used to reduce potential negative consequences.