# Human olfactory sensitivity varies across geographical locations

## TL;DR

This study shows that people's ability to detect smells varies depending on where they live, with location being a significant factor.

## Contribution

The study provides empirical evidence that geographical location significantly influences olfactory sensitivity.

## Key findings

- Location accounts for 17–20% of the variance in chemosensory sensitivity.
- Demographic and psychological factors explain 1.6–2.9% of the variance in chemosensory sensitivity.
- Olfactory sensitivity varies across geographical regions.

## Abstract

It has been assumed that olfactory sensitivity is relatively consistent in different populations worldwide. Emerging, yet fragmented evidence lends credit to the hypothesis that olfactory sensitivity may be geographically diverse. To gain deeper insight regarding the interplay between geographical, demographic, and health factors in the context of olfactory sensitivity, we conducted a multicenter study comprising data from 1046 participants inhabiting 19 locations around the world. Our results revealed that location accounted for 17–20% of the variance in chemosensory sensitivity. Demographic and psychological factors related to working memory and depressive symptoms also contribute to explaining sensitivity to odors, accounting for 1.6–2.9% of the variance in chemosensory sensitivity. Thus, we conclude that inhabitants of different geographical regions may present different sensitivities to chemical stimuli. We discuss the factors that could potentially be included in future investigations to pinpoint even more precisely what factors determine differences in chemosensory sensitivity around the globe.

The online version contains supplementary material available at 10.1038/s41598-026-38727-w.