Body odour disgust sensitivity is associated with xenophobia: evidence from nine countries across five continents.

Body odour disgust sensitivity (BODS) reflects a behavioural disposition to avoid pathogens, and it may also involve social attitudes. Among participants in the USA, high levels of BODS were associated with stronger xenophobia towards a fictitious refugee group. To test the generalizability of this finding, we analysed data from nine countries across five continents (N = 6836). Using structural equation modelling, we found support for our pre-registered hypotheses: higher BODS levels were associated with more xenophobic attitudes; this relationship was partially explained by perceived dissimilarities of the refugees' norms regarding hygiene and food preparation, and general attitudes toward immigration. Our results support a theoretical notion of how pathogen avoidance is associated with social attitudes: 'traditional norms' often involve behaviours that limit inter-group contact, social mobility and situations that might lead to pathogen exposure. Our results also indicate that the positive relationship between BODS and xenophobia is robust across cultures.

Perceptual odor qualities predict successful odor identification in old age.

Odor identification is a common assessment of olfaction, and it is affected in a large number of diseases. Identification abilities decline with age, but little is known about whether there are perceptual odor features that can be used to predict identification. Here, we analyzed data from a large, population-based sample of 2,479 adults, aged 60 years or above, from the Swedish National study on Aging and Care in Kungsholmen. Participants performed both free and cued odor identification tests. In a separate experiment, we assessed perceived pleasantness, familiarity, intensity, and edibility of all odors in the first sample, and examined how odor identification performance is associated with these variables. The analysis showed that high-intensity odors are easier to identify than low-intensity odors overall, but also that they are more susceptible to the negative repercussions of old age. This result indicates that sensory decline is a major aspect of age-dependent odor identification impairment, and suggests a framework where identification likelihood is proportional to the perceived intensity of the odor. Additional analyses further showed that high-performing individuals can discriminate target odors from distractors along the pleasantness and edibility dimensions and that unpleasant and inedible odors show smaller age-related differences in identification. Altogether, these results may guide further development and optimization of brief and efficient odor identification tests as well as influence the design of odorous products targeted toward older consumers.