# The perception of gender in two allegedly sex-specific body odor compounds MSH and HMHA

Camille Ferdenzi, Geraldine Coppin, Christophe Bousquet, Sylvain Delplanque

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Camille Ferdenzi, Geraldine Coppin, Christophe Bousquet, Sylvain Delplanque. The perception of gender in two allegedly sex-specific body odor compounds MSH and HMHA. 2024. hal-04747568

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The perception of gender

in two allegedly sex-specific body odor compounds MSH and HMHA

Camille Ferdenzi¹, Géraldine Coppin²,³, Bousquet Christophe¹,⁴, Sylvain Delplanque³

¹ Lyon Neuroscience Research Center, CNRS UMR5292, INSERM U1028, Claude Bernard

University Lyon 1, Bron, France

² Department of Psychology, UniDistance Suisse, Brig, Switzerland

³ Swiss Center for Affective Sciences, University of Geneva, Geneva, Switzerland

⁴ Department of Psychology, University of Konstanz, Konstanz, Germany; Centre for the
Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany

Correspondence concerning this article should be addressed to Camille Ferdenzi, Université
Claude Bernard Lyon 1, CNRS, INSERM, Centre de Recherche en Neurosciences de Lyon
CRNL UMR5292 U1028, CH Le Vinatier, Bât. 462 Neurocampus, 95 bd Pinel, F-69675 Bron
Cedex, France, camille.ferdenzi@cnrs.fr, +33 481 10 65 22.
21 **Abstract**

22 3-methyl-3-sulfanylhexan-1-ol (MSH) and 3-hydroxy-3-methylhexanoic acid (HMHA) are two
23 allegedly sexually dimorphic compounds present in human sweat. While MSH is more
24 typically found in women, HMHA is more typically found in men. Here we investigated
25 whether it was possible to identify these two compounds as explicitly masculine or
26 feminine. We also investigated whether gender and age differences would suggest a
27 possible role of these compounds in opposite-sex attractiveness. To this end, we analyzed
28 the perceptual ratings of t-shirts impregnated with these odors by 2,716 individuals (62%
29 female) aged between 6 and 90, collected during a one-year museum exhibition. Analyses
30 with Bayesian mixed-effects models revealed that only women rated MSH as more feminine
31 than HMHA. However, this effect remained very small and Masculinity/Femininity ratings
32 were extremely variable among the population. Women also rated both odors as more
33 intense and less pleasant than men. Age related differences reflected the effect of
34 increasing experience with body odors, such as an increase in odor familiarity. The loss of
35 olfactory function with age, i.e. presbyosmia, was also reflected by decreased perceived
36 intensity and unpleasantness (at least for HMHA). Overall, the results are not in favor of a
37 role of MSH and/or HMHA in male-female attractiveness, however they do agree with the
38 known gender and age differences in odor perception. Future studies on the olfactory
39 determinants of human attractiveness would benefit from the identification of new sexually
40 dimorphic compounds and from using experimental designs where the effect of odors are
41 tested more implicitly.

42 **Keywords**

43 Olfaction, Body Odor, Attractiveness, Gender differences, Development.
# 1. Introduction

Human body odor is a complex chemical mixture that conveys biological information about individuals [1]. There is increasing evidence that other individuals are able to detect and process this information. For instance, body odor may provide information about genetic proximity [2,3], hormonal levels [4–6], sickness [7], even personality traits [8] and emotional states [9,10], and thus appears to regulate our social interactions [11]. In addition, body odor chemical composition varies with age [12,13], which leads to different perceptual qualities when participants evaluate samples from different age groups [14,15].

Nevertheless, research on human ability to discriminate the body odor of men and women remains inconclusive.

While some studies have found evidence that humans are able to identify body odor donors' gender from breath odor [16] and torso odor [17], the performances in doing so remained rather low. In a study using axillary odors, almost no rater performed above chance in assigning a gender category; Moreover, only 22% to 67% of the samples were correctly assigned to their gender category depending on the trials [18]. In another study only 20% to 32% of European participants (but 64% of Asian participants) were able to correctly categorize t-shirt owners' sex [17]. Also, intensity and pleasantness of the odors were found to influence gender categorization significantly, with stronger and more unpleasant odors being more likely to be categorized as male than female [18].

Analytical chemistry approaches provide contrasted conclusions as well. Although the chemical composition of human body odor is not fully known partly due to methodological limitations [19,20], a few studies have investigated gender differences. Some studies fail to
find any difference between male and female chemical profiles [12]. Other studies however
suggest that, in spite of the large interindividual variability, male and female body odors
may differ [21,22], although a consensus regarding the chemicals concerned is far from
being reached because studies are rare and methods are heterogeneous. In another study
investigating gender differences in major constituents of human sweat odor [23], men and
women were found to differ in the ratio of two precursors secreted in the armpit. The first
one leads to the formation of MSH (3-methyl-3-sulfanylhexan-1-ol), responsible for the
sulfurous onion-like odor of women's sweat. The second precursor leads to the formation of
the carboxylic acid HMHA (3-hydroxy-3-methylhexanoic acid), causing a cheesy rancid odor
in men's sweat. In female samples, MSH precursor was found in larger quantities and HMHA
precursor in smaller quantities on average than in male samples. Although interindividual
variability was huge with significant overlap between men and women, the ratio HMHA
precursor / MSH precursor was stable and 3 times higher in men than in women. In addition
to the quantitative differences in both precursors as a function of gender, men have the
potential to produce more HMHA than women because they possess a greater amount of
Corynebacteria [24], which are responsible for the formation of HMHA [25]. Finally, few
studies have been conducted on HMHA and MSH to investigate how they are perceived, and
whether HMHA is perceived differently by men and women remains inconclusive to date
(see [26] and [27] for differing results).

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In this experiment, we tested whether the more typically feminine compound MSH and the
more typically masculine compound HMHA, were perceived as such in an explicit task. The
task was simple (rating the odors on a scale from very masculine to very feminine), and was
implemented on a very large sample of men and women of all ages in a museum, over a
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period of one year. Interindividual differences in gender evaluation of the body odor

compounds were investigated, with a particular attention to the gender and age of the

raters.

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Gender differences in odor perception have been shown frequently [28]. Regarding odors in

general, women seem to perform better than men in odor identification and memory tasks

[29,30], although they do not necessarily have better detection skills [e.g., 27,28], and they

also display higher attention to odors [33–35]. For social odors in particular, women seem to

be more responsive to body odors than men (self-declared [36]; hedonic responses to

biological samples [37]) and to identify family members based on their smell more

accurately [38]. The present study investigates body odor compounds that are reported to

be sexually dimorphic, a characteristic that may have a particular relevance in mate choice

(as in other modalities, such as voices [39] or faces [40]). A few sexually dimorphic body

odor compounds have been studied in the past (androstenes), but their supposed role as

sex pheromones has never been shown [41,42] and the reasons leading scientists to focus

so much on these molecules alone have been criticized [42]. Therefore, our study will

contribute to the development of knowledge of other categories of sexually dimorphic body

odor compounds. We hypothesize that gender differences may occur, reflecting either a

general superiority of women in odor processing and/or specific odor processing related to

a role of the compounds in opposite-sex attractiveness (such as men's higher pleasantness

ratings of the female compound MSH and/or women's higher pleasantness ratings of the

male compound HMHA).

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Running head: Perception of sex-specific body odor compounds

Finally, developmental and ageing effects were also expected in this study. Indeed, it is likely that masculinity/femininity of a sweat odor is acquired through experience, and that such judgments become more accurate after puberty (see [43] for acquired responses to body odors through childhood and adolescence). If MSH and HMHA are relevant for mate choice, it may also be that the information they convey about gender is relevant only during the sexually active period of life, but not during childhood or in the elderly. Last but not least, an age-related decrease in olfactory abilities [30,44] due to the senescence of the olfactory system may occur and impact the participant's olfactory evaluations. Overall, the ability to categorize MSH and HMHA as being respectively female and male in our study is expected to be higher in young adults than in the other age groups.

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## 2. Methods

### 2.1. Participants

Between February 15, 2019 and February 23, 2020, a total of 23,236 individuals visited a museum exhibition about the human sense of smell at the Fondation Claude Verdan Musée de la main UNIL-CHUV (Lausanne, Switzerland). One of the interactive modules in the exhibition aimed to test whether it was possible to tell whether two different body odors were masculine or feminine. 2,836 visitors (1,744 women, Age M = 30.7, SD = 18.3; 1,092 men, Age M = 30.0, SD = 20.3) voluntarily and anonymously took part in this module over a period of 10 months<fnref n="1" />. In order to avoid the inclusion of inconsistent data in the analyses, we excluded participants who reported being older than 90 years (44 excluded), those not able to smell MSH or HMHA (67 excluded), and those whose answers were the minimum or

<footnote n="1">¹ The data collected during the first two months were not retained because the order of presentation of the compounds was fixed, introducing an *obvious* experimental bias. The correct collection after modification of the experiment presentation software (randomization of compounds delivery) started on 21 May 2019 and ended on 23 February 2020.</footnote>
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maximum scores on all questions (9 excluded). Analyses were performed on a final database

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of 2,716 individuals (1,685 females). The distribution of participants by age group and

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gender is presented in Table 1.

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<table><caption>**Table 1.** Characteristics of the participants (number, age in years: Mean ± Standard Deviation), by gender and age groups.</caption><thead><tr><th rowspan="2">Age group</th><th colspan="2">Women</th><th colspan="2">Men</th></tr><tr><th>N</th><th>Mean age ± SD</th><th>N</th><th>Mean age ± SD</th></tr></thead><tbody><tr><td>6 to 9</td><td>123</td><td>7.6 ± 1.1</td><td>105</td><td>7.5 ± 1.2</td></tr><tr><td>10 to 19</td><td>448</td><td>14.2 ± 3.0</td><td>293</td><td>13.7 ± 2.9</td></tr><tr><td>20 to 29</td><td>292</td><td>24.7 ± 2.9</td><td>177</td><td>24.9 ± 2.7</td></tr><tr><td>30 to 39</td><td>333</td><td>34.4 ± 3.0</td><td>197</td><td>34.5 ± 3.2</td></tr><tr><td>40 to 49</td><td>261</td><td>43.9 ± 2.8</td><td>142</td><td>44.2 ± 2.9</td></tr><tr><td>50 to 59</td><td>122</td><td>53.9 ± 2.7</td><td>69</td><td>53.6 ± 2.6</td></tr><tr><td>60 to 69</td><td>80</td><td>64.2 ± 3.2</td><td>29</td><td>64.0 ± 2.8</td></tr><tr><td>70 to 90</td><td>26</td><td>73.8 ± 3.7</td><td>19</td><td>73.8 ± 4.9</td></tr></tbody></table>

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This study has been conducted in compliance with the rules of the University of Geneva and

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the Swiss National Science Foundation. Although this project has not been reviewed by an

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independent ethics committee, the strict ethical standards set out in The European Code of

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Conduct for Research Integrity (https://allea.org/portfolio-item/european-code-of-conduct-

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2023/) and the WMA declaration of Helsinki (https://www.wma.net/policies-post/wma-

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declaration-of-helsinki-ethical-principles-for-medical-research-involving-human-subjects/)

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were applied. The scientific relevance of the question was assessed by the authors of the

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publication in accordance with the state of the literature at the time. The protocol

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implemented enables the authors to answer the question posed while minimizing any

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inconvenience. Visitors' participation was voluntary, they were given information about the

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purpose of the study, they could end their participation at any time without any

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consequences and no personal data was collected.

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## 2.2. Odorants
One percent solutions of MSH (3-methyl-3-sulfanylhexan-1-ol) and HMHA (3-hydroxy-3-methylhexanoic acid) in triacetin, provided by Firmenich, S.A., were diluted respectively 50 times and 5 times in water, leading to a final concentration of 0.02% of MSH and 0.2% of HMHA. Each compound was sprayed (one squeeze, 0.116 ± 0.007 mL) three times a week (Tuesday, Thursday and Saturday), onto a separated piece of cotton cloth (about 10 x 10 cm) cut from a unique plain white T-shirt (renewed between the 10th and 15th of each month). These cloths were then placed at the bottom of two separate glass jars (10 cm diameter, 12 cm height, 188.5 cm³) and hermetically sealed with a cork. This procedure resulted in two well-perceived odors of fairly similar perceived intensity (as evaluated by a small group of 5 expert colleagues working at Firmenich, S.A.). These relatively high and supraliminal concentrations (see [27] for HMHA detection threshold), although not corresponding to naturally-occurring concentrations in body odor, were chosen to enable conscious perception.

## 2.3. Procedure

Visitors to the exhibition who wished to participate freely in this experiment sat on the stool positioned in front of the experimental setup (Figure 1). They then began the experiment by touching the touch screen on which was written: "Like the smell of sweat... By participating in the following test, you are taking part in a scientific study. Your responses are anonymous and will only be used in this scientific research conducted by the Swiss Center for Affective Sciences of the University of Geneva". They were invited to provide their gender and age, then to open one of the two jars (random order given by the presentation software), to smell the content, replace the cork and then answer a series of questions using 10-point scales presented on the touch screen. The questions were: [Masculinity/Femininity] How
181 would you describe this smell? (from 0 = very masculine to 10 = very feminine);

182 [Masculinity/Femininity Certainty] Are you sure of your choice? (0 = not at all, 10 = quite sure); [Pleasantness] Do you like this smell? (0 = not at all, 10 = a lot); [Intensity] How intense is this smell? (0 = I cannot smell it, 10 = very strong); [Familiarity] Do you know this smell? (0 = unknown smell, 10 = very familiar smell); [Typicality] For you, does this correspond to typical smell of sweat? (Yes / No). At the very end of the experiment, the participants could read on the screen: "Thank you for your participation. This scientific research will attempt to answer the following question: Is there a typically masculine or feminine smell of sweat?".

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<figure><img src="image_2.png" /><figcaption>190

**Figure 1.** Photograph of the experimental setting in the museum exhibition, including a stool, the two jars and the touch screen to record the participants' answers.</figcaption></figure>

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194 **2.4. Statistical analyses**

195 Data and analyses scripts (performed in R version 4.3.1 [42]) can be downloaded at

196 https://osf.io/hdtm7/.

197 To analyze the gender ratings of the odors MSH and HMHA as well as their modulating

198 factors, we used cumulative link mixed effects models (aka ordinal mixed effects
199 regressions) in the Bayesian framework with the brms R package [46]. The response variable 200 was the Masculinity/Femininity rating of the odor, an ordinal factor (a Likert-scale) that 201 could take one of eleven values between 0 and 10. The fixed part of the model contained 202 the participants' socio-demographic characteristics (Rater Age and Rater Gender), the 203 Compound presented (MSH or HMHA) and its interactions with Rater Age and Rater Gender, 204 and the participant's other odor ratings (Masculinity/Femininity, Pleasantness, Intensity, 205 Familiarity and Typicality). Subject's ID (allowing for individual differences in response to the 206 compound) and compound Presentation Order (first or second) were included in the model 207 as random factors. Additionally, we added a random slope for Compound (MSH or HMHA) 208 to allow for interindividual variation in response to compounds. To facilitate interpretation 209 of the coefficients, all numerical variables (Age, Pleasantness, Intensity and Familiarity) were 210 scaled. As the relationship between Intensity of the odor and its Masculinity/Femininity 211 score was non-linear, we added a quadratic term for Intensity. The binary predictors 212 (Gender, Compound and Typicality of the odor) were treated as factors, with two levels 213 each (Women and Men for Gender, with Women being the reference level; HMHA and MSH 214 for Compound, with HMHA being the reference level; Not typical and Typical for Typicality 215 of the odor, with Not typical being the reference level). As we used a Bayesian framework, 216 we compared models using the Leave-One-Out Information Criterion (looIC), with lower 217 values indicating better fit [47]. The Leave-One-Out Information Criterion (looIC) of the full 218 model with a quadratic term for Intensity (looIC = 24308.8) was much lower than the looIC 219 of the full model with a linear relationship for Intensity (looIC = 24369.5), supporting the 220 choice of the quadratic term. The full model can be read as follows:
221 Masculinity/Femininity ~ Rater Gender + Rater Age + Compound + Rater Gender ' Compound
222 + Rater Age ' Compound + Pleasantness + Intensity + Intensity^2 + Familiarity + Typicality +
223 (1 + Compound/SubjectID) + (1/Presentation Order).

224 Besides the full model described above, we also ran a reduced model excluding all variables
225 for which the direction of the effect was not highly certain (i.e., the posterior distribution
226 has at least 10% of its distribution going in the opposite direction to the median), a common
227 practice to avoid overfitting [48]. The reduced model can be read as follows:

228 Masculinity/Femininity ~ Rater Gender + Rater Age + Compound + Rater Gender ' Compound
229 + Pleasantness + Intensity + Intensity^2 + Typicality + (1 + Compound/SubjectID) +
230 (1/Presentation Order).

231 We also conducted analyses for the determinants of four other assessments of the odor: its
232 pleasantness, familiarity, intensity, and the certainty of the participant's Masculinity/
233 Femininity judgment. Pleasantness, familiarity and certainty of Masculinity/Femininity rating
234 were each measured on a 11-point Likert scale and were treated as ordinal response
235 variables. Intensity was also originally measured on a 11-point Likert scale, but our inclusion
236 criteria removed the 67 cases in which participants reported an intensity of 0 (i.e., they were
237 not able to smell this odor) and so intensity was treated as a 10-point Likert scale. We ran
238 four separate cumulative link mixed effects models. The same random structure as earlier
239 was applied and we included Rater Gender, Rater Age, Compound, as well as the
240 interactions Rater Gender ' Compound and Rater Age ' Compound as fixed effects. Two
241 additional elements were included in the model concerning the certainty of
242 Masculinity/Femininity judgment: Gender-strength and Gender-strength ' Compound
243 interaction. Gender strength is the result of the transformation of the
244 Masculinity/Femininity scale (ranging from 0 to 10) into a scale ranging from 0 to 5, where 0
245 means gender-neutral odor (i.e., 5 on the original scale) and 5 means highly gendered odor
246 (i.e., either 0/very masculine or 10/very feminine on the original scale). Four reduced
247 models were derived from these four full models by removing all variables for which the
248 direction of the effect was not highly certain (i.e., they had an associated probability p <
249 0.90).

250 For all models, we ran 4 Markov chains in parallel, each with 6,000 iterations, of which the
251 first 2,000 were treated as warmup and were therefore not used for inference. Note that,
252 for all models, when factors were involved in significant interactions, main effects of these
253 factors were not interpreted. We report results from the reduced model within the Bayesian
254 framework by presenting the posterior median slope, its associated Median Absolute
255 Deviation (MAD), the 90% Bayesian Credible Interval (90% CI), the proportion of support for
256 positive or negative effects (p+ or p., respectively), as well as derived median and MAD
257 estimates of Cohen's d for the fixed effects [48]. Even though they come from different
258 frameworks, there is typically a linear relationship between the p-values of the frequentist
259 approach and the p+ or p. of the Bayesian approach, with thresholds of 0.05, 0.01 and 0.001
260 for p-values corresponding to thresholds of 0.95, 0.99 and 0.999 for p+ or p. [49]. Note that
261 when the whole posterior distribution for one parameter is of the same sign, then p+ or p. =
262 1. General guidelines for interpreting Cohen's d are: very large effect when d > 1.3, large
263 when d > 0.8, medium when d > 0.5 and small effect when d > 0.2 [50,51].

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265 3. Results

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3.1. Masculinity/Femininity of MSH and HMHA

267 For our main rating of interest, that is Masculinity/Femininity, we found a significant Rater
268 Gender · Compound interaction (Est. = -0.22 ± 0.10, 90% CI [-0.38; -0.04], p. = 0.9826;
Table 2), since women are slightly more likely to rate MSH as more feminine (less masculine) than HMHA while there was no difference between the two compounds in male raters (Fig. 2A). There was also an effect of Rater Age (Est. = 0.05 ± 0.03, 90% CI [0.01; 0.10], p+ = 0.9756; Table 2), with older participants rating the odors as more feminine (less masculine) than younger ones (Fig. 2B). However, these effects remain very small (absolute value of Cohen's *ds* < 0.12; Table 2).

To further qualify these results with the rating of Certainty, we found that the participants were more confident in their Masculinity/Femininity rating when they perceived the odor as very gendered (very masculine or very feminine) than when they rated it as gender-neutral (Odor Gender-strength: Est. = 1.28 ± 0.04, 90% CI [1.21; 1.35], p+ = 1; Table 2 and Fig. 3A), and this effect was of medium size (Cohen's *d* = 0.71; Table 2). Also, confidence was higher for MSH than for HMHA (Fig. 3B), higher for men than for women (Fig. 3C), and decreased with age (Fig. 3D), although these effects remained very small (Gender effect: Est. = 0.17 ± 0.10, 90% CI [0.01; 0.33], p+ = 0.9575; Compound effect: Est. = 0.20 ± 0.05, 90% CI [0.11; 0.28], p+ = 1; Age effect: Est. = -0.17 ± 0.05, 90% CI [-0.25; -0.09], p. = 0.9996; Cohen's *ds* < 0.11; Table 2).

As for the other odor ratings, we found that the most prominent predictor of Masculinity/Femininity rating was Pleasantness (Est. = 0.44 ± 0.03, 90% CI [0.39; 0.49], p+ = 1; Table 2), with a small effect size (Cohen's *d* = 0.24; Table 2): The more pleasant the odor, the more likely it was to be evaluated as feminine (Fig. 2C). Some other effects were found, although they were very small (Cohen's *ds* < 0.14). First, there was an inverted U-shape relationship between Intensity and Masculinity/Femininity ratings (Est. = -0.17 ± 0.02, 90% CI [-0.20; -0.13], p. = 1; Table 2): Odors perceived as being of medium intensity (score around 5) were equally likely to be rated feminine or masculine, whereas odors perceived as
Running head: Perception of sex-specific body odor compounds

293 being of low or high intensity were rated as being more masculine (Fig. 2D). Second, odors
294 that were perceived as being more typical of sweat were rated as more masculine than
295 odors perceived as being less typical of sweat (Est. = -0.24 ± 0.06, 90% CI [-0.34; -0.15],
296 p- = 0.9999; Table 2 and Fig. 2E).

297

298 **Table 2.** Results of the reduced Bayesian linear mixed model on Masculinity/Femininity ratings and on
299 Certainty of the Masculinity/Femininity rating. The items in the "Variable" column are fixed factors, and
300 SubjectID (with a random slope for Compound) and Presentation Order were used as random factors. MAD:
301 Median Absolute Deviation, CI: Bayesian 90% Credible Interval (low and high boundaries), p+ or p-: probability
302 that the posterior distribution has the same effect direction than the estimate. Variables are sorted according
303 to the absolute value of their Cohen's d. Main effects involved in interactions (Int) are presented but not
304 interpreted. Higher values of the estimates indicate higher probabilities to rate an odor as more feminine.
305 Lines with minus (-) signs display variables that were removed in the reduced model. For each variable, the
306 estimate and the limits of the 90% CI correspond respectively to the dot and the limits of the thin line in
307 Fig. 2F.

<table><thead><tr><th>Variable</th><th>Estimate<br>[median]</th><th>Estimate error<br>[MAD]</th><th>90% CI<br>[low]</th><th>90% CI<br>[high]</th><th>p+ or p-</th><th>Cohen's d<br>[median]</th><th>Cohen's d<br>[MAD]</th></tr></thead><tbody><tr><td><strong>MASCULINITY/FEMININITY</strong></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Pleasantness</td><td>0.44</td><td>0.03</td><td>0.39</td><td>0.49</td><td>1.0000</td><td>0.2433</td><td>0.0171</td></tr><tr><td>Intensity [linear]</td><td>-0.37</td><td>0.04</td><td>-0.44</td><td>-0.30</td><td>1.0000</td><td>-0.2058</td><td>0.0236</td></tr><tr><td>Typicality [ref: Not typical]</td><td>-0.24</td><td>0.06</td><td>-0.34</td><td>-0.15</td><td>0.9999</td><td>-0.1351</td><td>0.0317</td></tr><tr><td>Rater Gender ' Compound</td><td>-0.22</td><td>0.10</td><td>-0.38</td><td>-0.04</td><td>0.9826</td><td>-0.1191</td><td>0.0575</td></tr><tr><td>Intensity [quadratic]</td><td>-0.17</td><td>0.02</td><td>-0.20</td><td>-0.13</td><td>1.0000</td><td>-0.0914</td><td>0.0115</td></tr><tr><td>Rater Age</td><td>0.05</td><td>0.03</td><td>0.01</td><td>0.10</td><td>0.9756</td><td>0.0296</td><td>0.0117</td></tr><tr><td>Rater Gender [ref: Women]</td><td>0.22</td><td>0.07</td><td>0.10</td><td>0.33</td><td>Int</td><td>Int</td><td>Int</td></tr><tr><td>Compound [ref: HMHA]</td><td>0.17</td><td>0.06</td><td>0.07</td><td>0.28</td><td>Int</td><td>Int</td><td>Int</td></tr><tr><td>Rater Age ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Familiarity</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td><strong>CERTAINTY of the masculinity/femininity rating</strong></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Odor Gender-strength</td><td>1.28</td><td>0.04</td><td>1.21</td><td>1.35</td><td>1.0000</td><td>0.7054</td><td>0.0232</td></tr><tr><td>Compound [Ref: HMHA]</td><td>0.20</td><td>0.05</td><td>0.11</td><td>0.28</td><td>1.0000</td><td>0.1083</td><td>0.0281</td></tr><tr><td>Rater Gender [Ref: Women]</td><td>0.17</td><td>0.10</td><td>0.01</td><td>0.33</td><td>0.9575</td><td>0.0936</td><td>0.0537</td></tr><tr><td>Rater Age</td><td>-0.17</td><td>0.05</td><td>-0.25</td><td>-0.09</td><td>0.9996</td><td>-0.0912</td><td>0.0266</td></tr><tr><td>Rater Gender ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Rater Age ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Odor Gender-strength ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr></tbody></table>

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<figure><img src="image_3.png" /></figure>

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<figure><img src="image_8.png" /><figcaption>**Figure 2.** Effect of (A) the Rater Gender × Compound interaction, (B) Rater Age, (C) Pleasantness rating, (D) Intensity rating and (E) Typicality on Masculinity/Femininity ratings (0 = Masculine in blue, 10 = Feminine in orange; expressed in cumulative probability to receive a given score). (F) Log odds-ratio for each variable retained in the reduced model, with the Masculinity/Femininity rating of the odor as the response variable. Dots, thick lines and thin lines represent the mean, the 50% Credible Interval [CI] and the 90% CI, respectively. Thin lines not crossing the black vertical line at x = 0 indicate that at least 90% of the posterior distribution of that variable has the same sign (which is equivalent to a significance level of 0.10 in the frequentist framework). For continuous variables (e.g. Pleasantness), positive posterior distributions indicate that high values on that variable are associated with high ratings of femininity. Conversely, negative posterior distributions indicate that high values on that variable are associated with low ratings of femininity. For categorical variables (e.g. Gender), positive posterior distributions indicate that the category that is not the reference (e.g. Men) give higher ratings of femininity than the reference category. Conversely, negative posterior distributions indicate that the category that is not the reference give lower ratings of femininity than the reference category. Interactions and quadratic terms are easier to interpret by looking at panels A and D. Variables are sorted according to the absolute value of their Cohen's *d* (highest on top).</figcaption></figure>
<figure><img src="image_9.png" /></figure>

<figure><img src="image_10.png" /></figure>

<figure><img src="image_11.png" /></figure>

<figure><img src="image_12.png" /></figure>

<figure><img src="image_13.png" /><figcaption>**Figure 3.** Effect of (A) Odor Gender-strength, (B) Compound, (C) Rater Gender, (D) Rater Age on the ratings of Certainty of the Masculinity/Femininity response (from 0 = low to 10 = high; expressed in cumulative probability to receive a given score). (E) Log odds-ratio for each variable retained in the reduced model, with the Certainty rating as the response variable. Dots, thick lines and thin lines represent the mean, the 50% Credible Interval [CI] and the 90% CI, respectively (see legend of Fig. 2 for more details). Variables are sorted according to the absolute value of their Cohen's d (highest on top).</figcaption></figure>

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## 3.2. Pleasantness, Intensity, Familiarity

In this section focusing on the other odor ratings, only effects with Cohen's *d* > 0.2 are illustrated (Fig. 4; see Supplementary Material for the other effects). No significant Rater Gender · Compound interactions were found, only main effects of Gender for Intensity (Est. = -0.42 ± 0.09, 90% CI [-0.56; -0.28], p. = 1; Table 3), Familiarity (Est. = -0.37 ± 0.12, 90% CI [-0.56; -0.17], p. = 0.9989; Table 3), and – with the biggest effect size (Cohen's *d* = 0.40) – Pleasantness (Est. = 0.73 ± 0.10, 90% CI [0.57; 0.89], p+ = 1; Table 3). More specifically, women provided higher intensity (Fig. 4A) and familiarity ratings (Fig. S1A), as well as lower pleasantness ratings than men (Fig. 4B), independently of the odor compound sampled. We found a significant Rater Age · Compound interactions for Intensity (Est. = 0.26 ± 0.06, 90% CI [0.17; 0.36], p+ = 1; Table 3), and for Pleasantness (Est. = -0.31 ± 0.06, 90% CI [-0.41; -0.21], p. = 1; Table 3). The perceived intensity tended to increase with age for MSH and to decrease for HMHA (Fig. S1B), and pleasantness tended to decrease with age for MSH while the reverse occurred for HMHA (Fig. S1C). Furthermore, the perceived familiarity of both compounds increased with age (Est. = 0.41 ± 0.06, 90% CI [0.32; 0.51], p+ = 1; Table 3 and Fig. 4C), and MSH elicited higher familiarity ratings than HMHA (Est. = 0.49 ± 0.06, 90% CI [0.38; 0.59], p+ = 1; Table 3 and Fig. 4D).

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<table><caption>**Table 3.** Results of the three reduced Bayesian linear mixed models on Intensity, Familiarity, and Pleasantness. The items in the "Variable" column are fixed factors, and SubjectID (with a random slope for Compound) and Presentation Order were used as random factors. MAD: Median Absolute Deviation, CI: Bayesian 90% Credible Interval (low and high boundaries), p+ or p-: probability that the posterior distribution has the same effect direction than the estimate. Variables are sorted according to the absolute value of their Cohen's d. Main effects involved in interactions (Int) are presented but not interpreted. Higher values of the estimates indicate higher probabilities to rate an odor as more intense, familiar, pleasant, or to rate the odor femininity/masculinity with higher certainty, respectively. Lines with minus (-) signs display variables that were removed in the reduced model. For each variable, the estimate and the limits of the 90% CI correspond respectively to the dot and the limits of the thin line in Fig. S2.</caption><thead><tr><th>Variable</th><th>Estimate<br>[median]</th><th>Estimate error<br>[MAD]</th><th>90% CI<br>[low]</th><th>90% CI<br>[high]</th><th>p, or p.</th><th>Cohen's d<br>[median]</th><th>Cohen's d<br>[MAD]</th></tr></thead><tbody><tr><td><strong>INTENSITY</strong></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Rater Gender [Ref: Women]</td><td>-0.42</td><td>0.09</td><td>-0.56</td><td>-0.28</td><td>1.0000</td><td>-0.2310</td><td>0.0476</td></tr><tr><td>Rater Age ' Compound</td><td>0.26</td><td>0.06</td><td>0.17</td><td>0.36</td><td>1.0000</td><td>0.1445</td><td>0.0310</td></tr><tr><td>Rater Age</td><td>-0.05</td><td>0.05</td><td>-0.13</td><td>0.04</td><td>Int</td><td>Int</td><td>Int</td></tr><tr><td>Compound [Ref: HMHA]</td><td>0.49</td><td>0.06</td><td>0.40</td><td>0.60</td><td>Int</td><td>Int</td><td>Int</td></tr><tr><td>Rater Gender ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td><strong>FAMILIARITY</strong></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Compound [Ref: HMHA]</td><td>0.49</td><td>0.06</td><td>0.38</td><td>0.59</td><td>1.0000</td><td>0.2840</td><td>0.0279</td></tr><tr><td>Rater Age</td><td>0.41</td><td>0.06</td><td>0.32</td><td>0.51</td><td>1.0000</td><td>0.2117</td><td>0.0288</td></tr><tr><td>Rater Gender [Ref: Women]</td><td>-0.37</td><td>0.12</td><td>-0.56</td><td>-0.17</td><td>0.9989</td><td>-0.1794</td><td>0.0580</td></tr><tr><td>Rater Gender ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td>Rater Age ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr><tr><td><strong>PLEASANTNESS</strong></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Rater Gender [Ref: Women]</td><td>0.73</td><td>0.10</td><td>0.57</td><td>0.89</td><td>1.0000</td><td>0.4031</td><td>0.0531</td></tr><tr><td>Rater Age ' Compound</td><td>-0.31</td><td>0.06</td><td>-0.41</td><td>-0.21</td><td>1.0000</td><td>-0.1706</td><td>0.0330</td></tr><tr><td>Rater Age</td><td>0.22</td><td>0.05</td><td>0.13</td><td>0.30</td><td>Int</td><td>Int</td><td>Int</td></tr><tr><td>Compound [Ref: HMHA]</td><td>-0.20</td><td>0.08</td><td>-0.33</td><td>-0.07</td><td>Int</td><td>Int</td><td>Int</td></tr><tr><td>Rater Gender ' Compound</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td><td>-</td></tr></tbody></table>

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<caption>**Figure 4.** Effect of Rater Gender on Intensity (A) and Pleasantness ratings (B). Effect of Rater Age on Familiarity ratings (C). Effect of Compound on Familiarity (D). Ratings (0 = low, 10 = high) are expressed in cumulative probability to receive a given score.</caption>
362 **Discussion**

363 Using a very large sample of men and women of all ages attending a museum exhibition, 364 this study aimed to investigate how two body odor compounds reported to be emitted in 365 sexually dimorphic amounts (the “feminine” compound MSH and the “masculine” 366 compound HMHA) were perceived.

367

368 The main question tested was whether MSH was perceived as more feminine than HMHA, 369 and conversely HMHA as more masculine than MSH. We found this to be the case only in 370 women, although they were less confident in their ratings than men. However, this result is 371 qualified, because the size of the effect is very small despite the very large sample size 372 (N=2'716) due to very high variability, and because the scores are fairly non-gendered for 373 both compounds (i.e., mean score around 5) (see Supplementary Table S1). If we assume 374 that this effect is of practical interest, it seems likely that it reflects a better ability of women 375 to process body odors, and odors in general. Previous studies have shown that women 376 generally outperform men in all olfactory abilities [28] and in particular are better at 377 performing fine discrimination of body odors (e.g., recognizing the odor of familiar 378 individuals [17,38]). This interpretation of our results is supported by several additional 379 observations in our study. Firstly, we found that women rate the odors (without distinction 380 between the compounds) as more intense and less pleasant than the men. This is consistent 381 with previous recurrent findings on body odors [16,43,52] and unpleasant non-body odors 382 [37]. Secondly, other than for Masculinity/Femininity, no interaction was found between 383 gender and compound in this study, casting doubt on the possible role of HMHA and/or 384 MSH compounds in male-female attractiveness. In particular, one could have expected that 385 MSH would be more pleasant to men and/or that HMHA would be more pleasant to women
386 (pleasantness being usually strongly correlated with attractiveness), which was not
387 observed here. This is in line with our previous studies on HMHA, that was found to be less
388 [26] or equally pleasant [27] to women than to men, and that had no gender-specific effects
389 on the perception of faces in more implicit approaches [26].

390

391 Finally, the small effect size and huge variability observed in gender ratings of MSH and
392 HMHA in our study may also question our choice of these particular compounds. Indeed,
393 the fact that the quantities of these compounds' precursors were described as highly
394 variable from one individual to another (and as largely overlapping between men's and
395 women's sample) [23] may explain why the perceptual outcome was not obvious here.

396 Clearer effects might have been found using more realistic mixtures of HMHA+MSH (instead
397 of single compounds presented separately), each based on male and female ratios that were
398 reported to be stable and 3 times higher in men [23]. Also, it must be kept in mind that
399 HMHA and MSH were not found as 'the most sexually dimorphic molecules *among* a series
400 of body odor compounds (unlike very few other studies did, e.g. [21] who reported a series
401 of 15 'gender markers' found in complex body odor profiles). Rather, sex differences
402 happened to have been found for those compounds while they were investigated to
403 understand body malodor, what is more in a limited number of participants (24 men, 25
404 women). Consequently, it may be that other compounds (possibly not identified yet) may be
405 more sexually dimorphic, and thus more relevant, and would trigger more differentiated
406 gender ratings. A promising future path to identify such compounds could be to use
407 chemical analysis to identify not only the overall changes in body odor composition between
408 pre- and post-puberty [53], but also the compounds for which sexual dimorphism increases
409 after puberty.
410

411 As to the developmental effects of odor perception, in this study we found that, with
412 increasing age, the odors were rated as more feminine (although with lower levels of
413 confidence) and more familiar, probably due to increasing exposure [54]. Also, although
414 difficult to interpret, a different pattern of perceptual changes throughout life was found for
415 MSH, that became more intense and more unpleasant with age, and HMHA, that became
416 less intense and less unpleasant with age. The latter effect is consistent with the
417 presbyosmia and reduced negativity bias phenomena in aging [55,56]. Age related effects in
418 our study may also result from shifts occurring earlier in development, such as during
419 adolescence, as reported by several studies on body odors [57] and body odor compounds
420 [58]. Importantly, however, no interaction between age and compound was found for the
421 variable Masculinity/Femininity, which again does not allow us to argue in favor of a
422 function of these compounds in male-female attractiveness.

423

424 Collecting our data in a museum during an exhibition was a considerable asset in terms of
425 sample size and of representativeness of all age groups. It may also help diluting the effects
426 of factors that we have chosen, for parsimony reasons, not to control (non-binary gender
427 identity, sexual orientation, etc.). Such a methodological choice also has its drawbacks,
428 especially regarding the relative lack of control compared to a laboratory setting. However,
429 we limited as much as possible the bias related to this lack of control, a priori by placing the
430 odors in hermetically sealed jars carefully watched over by the museum staff who refreshed
431 the odors every two days, and a posteriori by removing the obviously irrelevant responses
432 (see excluded data in Section 2.1.). Moreover, the following findings are highly consistent
433 with the literature, which suggests that we can trust the quality of the collected data: i) the
434 developmental course of HMHA and MSH perception described in the previous paragraph
435 (Fig. S1B,C) is consistent with the well-known positive relationship between intensity and
436 unpleasantness of body and non-body odors [59–61]; ii) the significant increase of
437 familiarity of the odors with age (Fig.4C) is highly consistent with a well-documented effect
438 of exposure [54]; iii) the prominent gender differences found for several perceptual
439 variables are similar to those consistently reported in the literature on olfaction (see [28] for
440 a review).

441

442 The main conclusion of this large-scale study is that, although women perceive HMHA as
443 more masculine that MSH in accordance with the alleged sexual dimorphism of these
444 compounds, this effect is very small and there is little consensus in the cohort (huge
445 variability) on the gender rating of these compounds. The results agree with the existing
446 literature regarding women's advantage in odor (and particularly social odor) processing
447 and age-related perceptual responses reflecting repeated exposure effects, but fail to
448 support the hypothesis that HMHA and/or MSH could be involved in male-female
449 attractiveness. Among the possible perspectives to understand the olfactory determinants
450 of male-female attractiveness [20], a better knowledge of the chemical composition of
451 human body odor (and of its variations as a function of sex and age) would help identifying
452 other possible relevant compounds. Also more ecological approaches where compounds are
453 not presented in an isolated manner but rather as mixtures (e.g. HMHA/MSH in a certain
454 ratio) or embedded in a "baseline body odor" may be helpful, as may experimental designs
455 where the outcome variables are not only explicit but also implicit, such as a behavior or a
456 physiological response.

457
458 Acknowledgments

459 The authors thank Olivier Glassey, Carolina Liebling and Roxanne Currat, as well as the
460 entire staff of Fondation Claude Verdan Musée de la Main in Lausanne (Switzerland), who
461 ensured the smooth running of the data collection. The authors also thank Christian
462 Starkenmann and all the members of the Perception and Bioresponses Department of the
463 Research and Development Division of Firmenich, SA, for their precious advice and their
464 theoretical and technical competence. Halina B. Stanley is thanked for English proofreading.

465 The Swiss National Science Foundation funded this research (Grant AGORA n°178467 to SD
466 and GC) and had no involvement in study design; in the collection, analysis and
467 interpretation of data; in the writing of the report; or in the decision to submit the article for
468 publication.

469

470 Author contributions

471 Camille Ferdenzi: Validation; Writing - original draft; Writing - review & editing.

472 Géraldine Coppin: Conceptualization; Data curation; Funding acquisition; Investigation;

473 Methodology; Supervision; Validation; Writing - review & editing.

474 Christophe Bousquet: Formal analysis; Visualization; Writing - original draft; Writing - review
475 & editing.

476 Sylvain Delplanque: Conceptualization; Data curation; Funding acquisition; Investigation;

477 Methodology; Project administration; Supervision; Validation; Writing - review & editing.

478
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**Figure S1.** Effect of Rater Gender on Familiarity ratings (A). Effect of the Rater Age × Compound interaction on Intensity (B) and Pleasantness ratings (C). Ratings (0 = low, 10 = high) are expressed in cumulative probability to receive a given score.

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<figure><img src="image_21.png" /></figure>

B. Familiarity

<figure><img src="image_22.png" /></figure>

C. Pleasantness

<figure><img src="image_23.png" /></figure>

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**Figure S2.** Log odds-ratio for each variable retained in the reduced model, with the Intensity (A), Familiarity (B) and Pleasantness of the odor (C) as the response variable. Dots, thick lines and thin lines represent the mean, the 50% Credible Interval [CI] and the 90% CI, respectively. Thin lines not crossing the black vertical line at x = 0 indicate that at least 90% of the posterior distribution of that variable has the same sign (which is equivalent to a significance level of 0.10 in the frequentist framework). Positive posterior distributions indicate that high values on that variable are associated with high ratings. Conversely, negative posterior distributions indicate that high values on that variable are associated with low ratings. Variables are sorted according to the absolute value of their Cohen's d (highest on top).
<table><caption>**Table S1.** Mean ± Standard Deviation of the Masculinity/Femininity ratings and of the Certainty of the Masculinity/Femininity ratings for each compound (MSH, HMHA), by Rater Gender and Rater Age group and for All groups combined.</caption><thead><tr><th rowspan="2"></th><th colspan="2">Masculinity/Femininity</th><th colspan="2">Certainty of the Masculinity/Femininity rating</th></tr><tr><th>MSH</th><th>HMHA</th><th>MSH</th><th>HMHA</th></tr></thead><tbody><tr><td><em>Women</em></td><td></td><td></td><td></td><td></td></tr><tr><td>6 to 9</td><td>4.34 ± 3.38</td><td>4.17 ± 3.15</td><td>6.38 ± 3.11</td><td>5.98 ± 3.21</td></tr><tr><td>10 to 19</td><td>4.40 ± 3.83</td><td>3.87 ± 3.67</td><td>7.29 ± 3.17</td><td>6.92 ± 3.32</td></tr><tr><td>20 to 29</td><td>4.30 ± 3.27</td><td>4.00 ± 3.08</td><td>6.19 ± 3.09</td><td>5.93 ± 3.18</td></tr><tr><td>30 to 39</td><td>4.35 ± 3.25</td><td>4.15 ± 2.99</td><td>6.38 ± 3.12</td><td>5.92 ± 3.19</td></tr><tr><td>40 to 49</td><td>4.26 ± 3.36</td><td>4.22 ± 3.11</td><td>6.14 ± 3.05</td><td>5.66 ± 3.09</td></tr><tr><td>50 to 59</td><td>4.45 ± 3.38</td><td>4.15 ± 3.13</td><td>6.48 ± 3.11</td><td>6.33 ± 3.21</td></tr><tr><td>60 to 69</td><td>4.70 ± 3.72</td><td>4.53 ± 3.34</td><td>6.60 ± 3.19</td><td>5.70 ± 3.24</td></tr><tr><td>70 to 90</td><td>4.20 ± 3.44</td><td>4.99 ± 3.33</td><td>6.84 ± 2.83</td><td>5.93 ± 3.25</td></tr><tr><td><em>Men</em></td><td></td><td></td><td></td><td></td></tr><tr><td>6 to 9</td><td>4.55 ± 3.36</td><td>4.75 ± 3.15</td><td>6.56 ± 2.97</td><td>6.20 ± 3.03</td></tr><tr><td>10 to 19</td><td>4.59 ± 4.04</td><td>4.99 ± 3.74</td><td>7.41 ± 3.21</td><td>6.81 ± 3.46</td></tr><tr><td>20 to 29</td><td>4.36 ± 3.30</td><td>4.44 ± 3.26</td><td>6.82 ± 2.91</td><td>6.69 ± 2.96</td></tr><tr><td>30 to 39</td><td>4.81 ± 3.31</td><td>5.17 ± 2.98</td><td>6.47 ± 2.87</td><td>6.06 ± 2.83</td></tr><tr><td>40 to 49</td><td>4.70 ± 3.20</td><td>4.85 ± 2.86</td><td>5.95 ± 2.96</td><td>5.61 ± 2.92</td></tr><tr><td>50 to 59</td><td>4.15 ± 3.15</td><td>4.55 ± 3.01</td><td>6.49 ± 2.83</td><td>6.05 ± 2.97</td></tr><tr><td>60 to 69</td><td>5.55 ± 3.42</td><td>4.74 ± 3.17</td><td>6.49 ± 3.06</td><td>6.35 ± 3.03</td></tr><tr><td>70 to 90</td><td>3.97 ± 3.31</td><td>4.79 ± 2.91</td><td>6.38 ± 2.87</td><td>5.24 ± 2.95</td></tr><tr><td><em>All</em></td><td>4.42 ± 3.37</td><td>4.39 ± 3.16</td><td>6.44 ± 3.06</td><td>6.07 ± 3.14</td></tr></tbody></table>
<table><caption>**Table S2.** Mean ± Standard Deviation of the Intensity, Familiarity and Pleasantness ratings, and % “yes” responses to the question “does this correspond to a typical smell of sweat?” for each compound (MSH, HMHA), by Rater Gender and Rater Age group and for All groups combined.</caption><thead><tr><th rowspan="2"></th><th colspan="2">Intensity</th><th colspan="2">Familiarity</th><th colspan="2">Pleasantness</th><th colspan="2">Typical of sweat</th></tr><tr><th>MSH</th><th>HMHA</th><th>MSH</th><th>HMHA</th><th>MSH</th><th>HMHA</th><th>MSH</th><th>HMHA</th></tr></thead><tbody><tr><td>Women</td><td>8.70 ± 1.79</td><td>8.25 ± 2.10</td><td>6.17 ± 3.12</td><td>5.58 ± 3.19</td><td>1.35 ± 2.40</td><td>1.43 ± 2.38</td><td>78%</td><td>68%</td></tr><tr><td>6 to 9</td><td>7.91 ± 2.65</td><td>7.77 ± 2.70</td><td>4.75 ± 3.88</td><td>3.98 ± 4.02</td><td>2.46 ± 3.28</td><td>1.91 ± 2.98</td><td>67%</td><td>61%</td></tr><tr><td>10 to 19</td><td>8.40 ± 1.92</td><td>8.25 ± 2.07</td><td>5.80 ± 3.12</td><td>5.14 ± 3.15</td><td>1.26 ± 2.42</td><td>1.13 ± 2.09</td><td>74%</td><td>66%</td></tr><tr><td>20 to 29</td><td>8.90 ± 1.60</td><td>8.39 ± 1.96</td><td>6.42 ± 2.74</td><td>5.90 ± 2.92</td><td>1.41 ± 2.42</td><td>1.35 ± 2.22</td><td>81%</td><td>69%</td></tr><tr><td>30 to 39</td><td>8.95 ± 1.49</td><td>8.32 ± 2.08</td><td>6.58 ± 2.93</td><td>5.83 ± 2.92</td><td>1.21 ± 2.08</td><td>1.48 ± 2.32</td><td>79%</td><td>68%</td></tr><tr><td>40 to 49</td><td>9.00 ± 1.48</td><td>8.42 ± 1.90</td><td>6.71 ± 2.93</td><td>6.28 ± 3.04</td><td>1.01 ± 2.08</td><td>1.40 ± 2.47</td><td>84%</td><td>76%</td></tr><tr><td>50 to 59</td><td>8.86 ± 1.87</td><td>8.34 ± 1.99</td><td>6.43 ± 3.23</td><td>6.13 ± 3.16</td><td>1.34 ± 2.32</td><td>1.77 ± 2.63</td><td>79%</td><td>71%</td></tr><tr><td>60 to 69</td><td>8.89 ± 1.24</td><td>7.91 ± 2.17</td><td>6.33 ± 3.31</td><td>5.74 ± 3.29</td><td>1.55 ± 2.67</td><td>1.94 ± 2.68</td><td>84%</td><td>68%</td></tr><tr><td>70 to 90</td><td>7.96 ± 2.07</td><td>6.88 ± 2.53</td><td>4.12 ± 3.17</td><td>3.62 ± 2.87</td><td>1.31 ± 1.76</td><td>1.92 ± 2.65</td><td>73%</td><td>54%</td></tr><tr><td>Men</td><td>8.37 ± 1.93</td><td>7.98 ± 2.16</td><td>5.86 ± 3.13</td><td>5.17 ± 3.21</td><td>1.88 ± 2.63</td><td>1.93 ± 2.58</td><td>74%</td><td>64%</td></tr><tr><td>6 to 9</td><td>8.23 ± 2.35</td><td>8.26 ± 2.45</td><td>3.93 ± 4.02</td><td>3.18 ± 3.80</td><td>2.46 ± 3.44</td><td>1.70 ± 2.93</td><td>70%</td><td>62%</td></tr><tr><td>10 to 19</td><td>8.14 ± 2.04</td><td>7.86 ± 2.22</td><td>5.23 ± 3.21</td><td>4.62 ± 3.26</td><td>2.00 ± 2.82</td><td>1.86 ± 2.66</td><td>66%</td><td>63%</td></tr><tr><td>20 to 29</td><td>8.16 ± 2.08</td><td>7.86 ± 2.20</td><td>6.52 ± 2.71</td><td>5.64 ± 2.97</td><td>1.96 ± 2.56</td><td>2.16 ± 2.51</td><td>77%</td><td>66%</td></tr><tr><td>30 to 39</td><td>8.67 ± 1.66</td><td>8.15 ± 2.05</td><td>6.41 ± 2.77</td><td>5.77 ± 2.85</td><td>1.50 ± 2.18</td><td>1.74 ± 2.36</td><td>77%</td><td>61%</td></tr><tr><td>40 to 49</td><td>8.61 ± 1.57</td><td>7.85 ± 1.95</td><td>6.82 ± 2.40</td><td>5.90 ± 2.72</td><td>1.62 ± 2.13</td><td>2.02 ± 2.40</td><td>83%</td><td>65%</td></tr><tr><td>50 to 59</td><td>8.83 ± 1.58</td><td>8.41 ± 1.87</td><td>6.17 ± 2.85</td><td>6.23 ± 2.84</td><td>1.96 ± 2.87</td><td>2.14 ± 2.79</td><td>84%</td><td>71%</td></tr><tr><td>60 to 69</td><td>8.41 ± 1.48</td><td>7.69 ± 2.41</td><td>6.93 ± 2.40</td><td>5.48 ± 3.02</td><td>2.07 ± 2.51</td><td>2.24 ± 2.47</td><td>86%</td><td>76%</td></tr><tr><td>70 to 90</td><td>8.21 ± 2.27</td><td>7.63 ± 2.54</td><td>4.58 ± 3.58</td><td>4.26 ± 3.78</td><td>1.21 ± 1.51</td><td>2.16 ± 2.93</td><td>63%</td><td>58%</td></tr><tr><td>All</td><td>8.58 ± 1.85</td><td>8.15 ± 2.13</td><td>6.05 ± 3.13</td><td>5.42 ± 3.20</td><td>1.55 ± 2.50</td><td>1.62 ± 2.47</td><td>77%</td><td>67%</td></tr></tbody></table>