The effect of complete caloric intake restriction on human body odour quality

Abstract

Previous studies on various vertebrates have shown that quantity and quality of food intake affect odour attractiveness as perceived by potential mates. In humans, the quality of body odour is similarly affected by ingested foods, such as by variation in meat and garlic intake. Nevertheless, it is not known whether quantity of food has an impact on human body odour attractiveness. Thus, here we tested how 48 hours of complete caloric intake restriction affects the hedonic quality of human axillary odour. Odour samples (cotton pads fixed in both armpits and worn for 12 hours) were obtained from healthy female donors across three conditions: i) during their habitual food regime; ii) after 48 hours of complete caloric intake restriction (drinking water was provided), and iii) 72 hours after restoration of caloric intake. Axillary samples were assessed by male raters regarding their pleasantness, attractiveness, femininity, and intensity. We also collected blood samples to assess physiological changes due to dietary restriction (e.g., glucose, sodium, albumin, triacylglyceride assays) and anthropometric measurements at the same intervals as body odour samples. We found no differences in pleasantness, attractiveness and intensity between the odour samples collected at baseline and during complete caloric intake restriction. Interestingly, we found that body odours were rated more pleasant, more attractive and less intense after restoration of food intake as compared to the baseline and during caloric restriction. Our results suggest that restoration of food intake positively influences hedonic quality of human body odour which might thus provide cues to current fitness status and metabolic efficiency.

Interdisciplinary challenges for elucidating human olfactory attractiveness

“…Compared with healthy donors, the odour of sick persons is more aversive [11] and more intensely activates brain networks involved in odour processing [44]. Information about body condition related to nutritional state is also conveyed by body odour [45], as well as about gender [46,47] and age [10]. Finally, body odours are involved in the communication of emotions (see also [48,49]; meta-analysis in [50]) and of personality traits (such as dominance and neuroticism) [51], both of which are involved in the initiation and maintenance of romantic relationships [52].…”

Losing stinks! The effect of competition outcome on body odour quality

“…To assess whether the collected ratings were accurate and stable estimates, we calculated the point of stability (POS, a point at which averages do not meaningfully change with incorporation of additional observations) within a corridor of stability of a mean (COS) [84,85] for each scale and rater's sex. We used the default setting as per Hehman et al [84] and the POS was specified as 95% of observed values falling within ± 0.5 COS of the 7-point scale we used. The number of raters met calculated POS values for all scales except for masculinity (POS = 37) and intensity (POS = 34) where samples collected before the match were assessed by 31 male raters (electronic supplementary material, table S1).…”

“…To assess whether the collected ratings were accurate and stable estimates, we calculated the point of stability (POS, a point at which averages do not meaningfully change with incorporation of additional observations) within a corridor of stability of a mean (COS) [84,85] for each scale and rater's sex. We used the default setting as per Hehman et al [84] and the POS was specified as 95% of observed values falling within ± 0.5 COS of the 7-point scale we used.…”

Body Odours Sampled at Different Body Sites in Infants and Mothers—A Comparison of Olfactory Perception

“…Nonetheless, according to this study, the microbial profile of polyester clothing rather leads to malodour [ 16 ]. In the previous literature, the most common sampling mediums are thus either cotton pads [ 13 , 17 , 18 , 19 ] or cotton t-shirts [ 8 , 12 ]. While t-shirts are simply worn by participants, cotton pads are usually fixed directly to their skin with surgical tape.…”

“…In view of human sweat physiology, the stage of development of the odour donor and, in particular, secretion of glands must be considered. In adults, the axilla is found as body site of choice when assessing odour-related perception with experimental paradigms [ 7 , 13 , 17 , 26 ].…”