Olfactory Capabilities Towards Food and Non-food Odours in Men and Women of Various Weight Statuses

Introduction Olfaction is a sense that is closely linked to food intake and food choices in humans, but its relationship with obesity remains equivocal in the scientific literature: overall olfactory capacities seem poorer in obesity compared to normal weight, but some authors observed that individuals with obesity might have a heightened sensitivity to food odours. Our objective was to evaluate olfactory capabilities for food and non-food odours. Methods The European Test for Olfactory Capabilities (ETOC) was used. This test measures suprathreshold olfactory detection and identification capabilities. One hundred twenty-four men and women were tested, of whom 41 individuals with normal-weight, 45 individuals with overweight, and 38 individuals with obesity. Results Contrary to the major current in the literature, no differences between the three weight status groups were found in either detection or identification capabilities, for food as well as for non-food odours. Age decreased detection score while being male decreased identification score. A trend for better identification of non-food odours was found for overweight and obesity vs. normal-weight. Conclusion We encourage further research to distinguish food and non-food odours in olfactory measurements related to weight status in order to replicate our findings on a larger set of odours. Implication Future research should also focus on sensitivity to food odours by estimating detection thresholds and to control for confounding variables such as hormonal status, as well as individual liking of the odours.