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Concept: Shaving


Negative frequency-dependent sexual selection maintains striking polymorphisms in secondary sexual traits in several animal species. Here, we test whether frequency of beardedness modulates perceived attractiveness of men’s facial hair, a secondary sexual trait subject to considerable cultural variation. We first showed participants a suite of faces, within which we manipulated the frequency of beard thicknesses and then measured preferences for four standard levels of beardedness. Women and men judged heavy stubble and full beards more attractive when presented in treatments where beards were rare than when they were common, with intermediate preferences when intermediate frequencies of beardedness were presented. Likewise, clean-shaven faces were least attractive when clean-shaven faces were most common and more attractive when rare. This pattern in preferences is consistent with negative frequency-dependent selection.

Concepts: Selection, Facial hair, Secondary sex characteristic, Shaving, Beard


Women’s preferences for men’s androgen dependent secondary sexual traits are proposed to be phenotypically plastic in response to exposure to pathogens and pathogen disgust. While previous studies report that masculinity in facial shape is more attractive to women who have recently been exposed to pathogenic cues and who are high in self-reported pathogen disgust, facial hair may reduce male attractiveness under conditions of high pathogens as beards are a possible breeding ground for disease carrying ectoparasites. In the present study, we test whether women’s preferences for beardedness and facial masculinity vary due to exposure to different pathogenic cues. Participants (N = 688, mean age + 1SD = 31.94 years, SD = 6.69, range = 18-67) rated the attractiveness of facial composite stimuli of men when they were clean-shaven or fully bearded. These stimuli were also manipulated in order to vary sexual dimorphism by ±50%. Ratings were conducted before and after exposure to one of four experimental treatments in which participants were primed to either high pathogens (e.g. infected cuts), ectoparasites (e.g. body lice), a mixture of pathogens and ectoparasites, or a control condition (e.g. innocuous liquids). Participants then completed the three-domain disgust scale measuring attitudes to moral, sexual and pathogen disgust. We predicted that women would prefer facial masculinity following exposure to pathogenic cues, but would show reduced preferences for facial hair following exposure to ectoparasites. Women preferred full beards over clean-shaven faces and masculinised over feminised faces. However, none of the experimental treatments influenced the direction of preferences for facial masculinity or beardedness. We also found no association between women’s self-reported pathogen disgust and their preferences for facial masculinity. However, there was a weak positive association between moral disgust scores and preferences for facial masculinity, which might reflect conservatism and preferences for gender typicality in faces. Women’s preferences for beards were positively associated with their pathogen disgust, which runs contrary to our predictions and may reflect preferences for high quality individuals who can withstand any costs of beardedness, although further replications are necessary before firm conclusions can be made. We conclude that there is little support for pathogenic exposure being a mechanism that underpins women’s directional preferences for masculine traits.

Concepts: Immune system, Bacteria, Microbiology, Gender, Man, Secondary sex characteristic, Shaving, Beard


Facial hair, like many masculine secondary sexual traits, plays a significant role in perceptions of an array of sociosexual traits in men. While there is consensus that beards enhance perceptions of masculinity, age, social dominance, and aggressiveness, the perceived attractiveness of facial hair varies greatly across women. Given the ease with which facial hair can be groomed and removed entirely, why should some men retain beards and others choose to remove them? We hypothesized that men with relatively sexist attitudes would be more likely to allow their facial hair to grow than men with less sexist attitudes. Men from the USA (n = 223) and India (n = 309) completed an online survey measuring demographic variables, ambivalent sexism, and facial hair status. After controlling for demographic variables, men with facial hair were significantly higher in hostile sexism than clean-shaven men; hostile sexism was a significant predictor of facial hair status over and above demographic variables; and facial hair was more frequent among ambivalent and hostile sexists than among benevolent and non-sexists. It is suggested that sexist men choose to grow facial hair because it maximizes sexual dimorphism and augments perceived masculinity and dominance.

Concepts: Gender, Gender role, Man, Masculinity, Sexism, Facial hair, Secondary sex characteristic, Shaving


Facial and body hair are some of the most visually conspicuous and sexually dimorphic of all men’s secondary sexual traits. Both are androgen dependent, requiring the conversion of testosterone into dihydrotestosterone via the enzyme 5α reductase 2 for their expression. While previous studies on the attractiveness of facial and body hair are equivocal, none have accounted as to how natural variation in their distribution may influence male sexual attractiveness. In the present study, we quantified men’s facial and body hair distribution as either very light, light, medium, or heavy using natural photographs. We also tested whether women’s fertility influenced their preferences for beards and body hair by comparing preferences among heterosexual women grouped according their fertility (high fertility, low fertility, and contraceptive use). Results showed that men with more evenly and continuously distributed facial hair from the lower jaw connecting to the mustache and covering the cheeks were judged as more sexually attractive than individuals with more patchy facial hair. Men with body hair were less attractive than when clean shaven, with the exception of images depicting some hair around the areolae, pectoral region, and the sternum that were significantly more attractive than clean-shaven bodies. However, there was no effect of fertility on women’s preferences for men’s beard or body hair distribution. These results suggest that the distribution of facial and body hair influences male attractiveness to women, possibly as an indication of masculine development and the synthesis of testosterone into dihydrotestosterone via 5α reductase.

Concepts: Gender, Testosterone, Physical attractiveness, Facial hair, Secondary sex characteristic, Shaving, Moustache, Beard


Beards in the operating room are controversial because of their potential to retain and transmit pathogenic organisms. Many bearded orthopedic surgeons choose to wear nonsterile hoods in addition to surgical masks to decrease contamination of the operative field. The goal of this study was to determine whether nonsterile surgical hoods reduce the risk of bacterial shedding posed by beards. Bearded (n=10) and clean-shaven (n=10) subjects completed 3 sets of standardized facial motions, each lasting 90 seconds and performed over blood agar plates, while unmasked, masked, and masked and hooded. The plates were cultured for 48 hours under aerobic and anaerobic conditions. Colony-forming units (CFUs) were quantified, expanded, and identified. Overall, the addition of surgical hoods did not decrease the total number of anaerobic and aerobic CFUs isolated per subject, with a mean of 1.1 CFUs while hooded compared with 1.4 CFUs with the mask alone (P=.5). Unmasked subjects shed a mean of 6.5 CFUs, which was significantly higher than the number of CFUs shed while masked (P=.02) or hooded (P=.01). The bearded group did not shed more than the clean-shaven group while unmasked (9.5 vs 3.3 CFUs, P=.1), masked (1.6 vs 1.2 CFUs, P=.9), or hooded (0.9 vs 1.3 CFUs, P=.6). Bearded surgeons did not appear to have an increased likelihood of bacterial shedding compared with their nonbearded counterparts while wearing surgical masks, and the addition of nonsterile surgical hoods did not decrease the amount of bacterial shedding observed. [Orthopedics.].

Concepts: Agar plate, Shaving, Beard


The impact of preoperative magnetic resonance imaging (pMRI) and cavity shave margins (CSM) on re-excision rate (RR) in DCIS is unclear. We investigated whether either modality was associated with RR in DCIS.

Concepts: Spin, Nuclear magnetic resonance, Magnetic resonance imaging, Ductal carcinoma, Shaving


Invasive traditional practices which are frequently harmful are common in the care of children including neonates in developing countries. We report two cases of evisceration of intra-abdominal viscera in two neonates subjected to abdominal scarification with razor blades following febrile illnesses. The greater omentum and a loop of jejunum, respectively, were eviscerated. Both were successfully managed and discharged home. Consent was obtained from the parents for the use of the photos. These cases highlight the dangers of invasive traditional practices on neonates and the urgent need for enlightenment campaigns as well as enactment of policies to help protect these children in developing countries.

Concepts: Health care, Developing country, Abdomen, Greater omentum, Cutting tools, Shaving, Razor


Following lumpectomy, full cavity shaving approach is used to reduce positive margin rates, among other issues previously studied by others, at an expense of increase in tissue volume removed. We present our experience after switching from full cavity shaving to a targeted shaving approach using MarginProbe, an intra-operative margin assessment device.

Concepts: Shaving


Shaving is an ubiquitous practice, and cutaneous irritation and inflammation are common sequelae, which may be worsened by underlying skin conditions or poor hair removal techniques. Moisturizing shaving creams and aftershaves are available to help maintain or restore the epidermal barrier; however, many continue to suffer from post-shave redness, itching, and pain. To reduce post-shave inflammation, some products have included botanical and other natural ingredients, which are often favored by consumers. We evaluated Bensal HP, an ointment containing 3% oak bark extract, 3% salicylic acid, and 6% benzoic acid, which has documented anti-inflammatory and antimicrobial properties, in a murine model of shave irritation to determine whether it would be useful in this clinical setting. Shaving dermatitis was simulated using a depilatory agent and electric clippers, and the shaved area was photographed and treated with Bensal HP daily for four days. Compared to untreated controls, mice treated with Bensal HP experienced a visible reduction in skin irritation and inflammation. These findings were mirrored on histology, as Bensal HP-treated areas demonstrated increased epidermal integrity and decreased dermal inflammatory infiltrate compared to untreated skin. Using immunohistochemistry, fewer neutrophils and macrophages were noted, and cytokine analysis also revealed decreased IL-6 in Bensal HP-treated skin at 24 and 96 hours after shaving. These results highlight the potential of Bensal HP as an anti-inflammatory treatment for shave irritation. Given the product’s application against a variety of inflammatory and infectious skin disorders, its use against shave irritation may also improve comorbid skin conditions, such as pseudofolliculitis barbae.

J Drugs Dermatol. 2016;15(7):836-840.

Concepts: Immune system, Inflammation, Skin, Anti-inflammatory, Irritation, Hair removal, Shaving, Pseudofolliculitis barbae


Globally, millions of men regularly remove their facial hair using an electric shaver. Over the course of several decades, the concept of an electric shaver has evolved from a relatively simple hand-powered apparatus to a technologically advanced device designed to provide the user with an optimum shaving experience. This requires a careful balance between robust removal of hair and skin comfort. By incorporating advanced scientific measurement and imaging technology into clinical testing, insights are being gained into skin comfort issues associated with hair removal practices. This study describes new research insights that have guided the development of electric shaving technology. These innovative features are designed to maximize hair removal and minimize the impact on skin health, thus enabling new levels of shaving efficacy and comfort to be attained.

Concepts: Science, Engineering, Technology, Creativity, Innovation, Facial hair, Shaving, Head shaving