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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


A barber shop is a potential place for non-sexual transmission of deadly blood borne diseases such as acquired immuno-deficient syndrome. Few researches have been conducted to assess the knowledge of barbers regarding human immunodeficiency virus (HIV) transmission in Pakistan. With majority of the population visiting roadside saloons, it is imperative to have local data in this regard. The objective of this study was to investigate the knowledge and practices of barbers with reference to razor use and steps taken to sterilize their instruments. A total of 300 barber saloons were conveniently selected for this cross-sectional study during a time period of 5 months from May 2012 till September 2012. The shops were categorized into three groups: big saloons, small saloons and roadside saloons based on the inclusion criteria. One barber was randomly selected as a representative from each saloon. Data collection from each barber shop was carried out by an interviewer using a pre-coded questionnaire. Majority of the barbers had low school education. Awareness regarding sharing of blades as a route of HIV transmission was known by 90 % (n = 90) of big saloon barbers with awareness decreasing in small (n = 55) and roadside saloon barbers (n = 27). Only 60.3 % (n = 181) of the barbers used new blades between customers. In comparison to big saloon barbers, the majority (n = 53) of roadside saloon barbers used tap water for cleaning purposes. Only 40 % of the roadside barbers used antiseptic after shaving. The results of our study indicate that roadside saloon barbers, to whom majority of Pakistani population visit, have inadequate awareness regarding HIV transmission. Their poor barbering practices were mainly due to their low education. This potentiates a great risk for aggravating the HIV endemic in Pakistan.

Concepts: HIV, AIDS, Immune system, Infectious disease, Shaving, Razor, Barber, 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


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 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 challenge of shaving is to cut the beard hair as closely as possible to the skin without unwanted effects on the skin. To achieve this requires the understanding of beard hair and male facial skin biology as both, the beard hair and the male facial skin, contribute to the difficulties in obtaining an effective shave without shaving-induced skin irritation. Little information is available on the biology of beard hairs and beard hair follicles. We know that, in beard hairs, the density, thickness, stiffness, as well as the rates of elliptical shape and low emerging angle, are high and highly heterogeneous. All of this makes it challenging to cut it, and shaving techniques commonly employed to overcome these challenges include shaving with increased pressure and multiple stroke shaving, which increase the probability and extent of shaving-induced skin irritation. Several features of male facial skin pose problems to a perfect shave. The male facial skin is heterogeneous in morphology and roughness, and male skin has a tendency to heal slower and to develop hyperinflammatory pigmentation. In addition, many males exhibit sensitive skin, with the face most often affected. Finally, the hair follicle is a sensory organ, and the perifollicular skin is highly responsive to external signals including mechanical and thermal stimulation. Perifollicular skin is rich in vasculature, innervation and cells of the innate and adaptive immune system. This makes perifollicular skin a highly responsive and inflammatory system, especially in individuals with sensitive skin. Activation of this system, by shaving, can result in shaving-induced skin irritation. Techniques commonly employed to avoid shaving-induced skin irritation include shaving with less pressure, pre- and post-shave skin treatment and to stop shaving altogether. Recent advances in shaving technology have addressed some but not all of these issues. A better understanding of beard hairs, beard hair follicles and male facial skin is needed to develop novel and better approaches to overcome the challenge of shaving. This article covers what is known about the physical properties of beard hairs and skin and why those present a challenge for blade and electric shaving, respectively.

Concepts: Skin, Hair, Hair follicle, Challenge, Facial hair, Sebaceous gland, 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