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Dr. Devendra Singh
• At University of Texas– Buss, Langlois, etc.
• Psychologist– Food and alcohol addiction
• Body image and dieting-related research led into his early waist-to-hip ratio studies
Body Image as Psychological Construct
• Multidimensional self-attitudes toward one’s body, particularly its appearance
• Self-perceptions, cognitions, affect, and behaviours
• Has moderate relationship with self-esteem and psychosocial adjustment issues– e.g., eating disturbances, depression, social
anxiety, sexual frustration
Psychology Today (1972 & 1985)
• Popular magazine– Mail-in survey
– Stratified random sample
• Found that women possess more negative body-image attitudes than men– Shape and weight
– Fears of becoming fat
– Occur across lifespan, but especially prevalent in adolescence
Cash & Henry (1995)
• 803 women• 18-70 years• 19 cities in 5 U.S.A. geographic regions• Representative cross-section of age, race,
income, education• Door-to-door; left questionnaire booklet to
be collected next day; monetary compensation
Subscales of the MB SRQ
• Appearance Evaluation (AE)– 7 items to assess global evaluation of appearance
• Body Areas Satisfaction Scale (BASS)– Height, weight, hair, face, upper-, mid-, and lower-torso
• Overweight Preoccupation (OP)– Weight vigilance, fat anxiety, current dieting, eating restraint
Results
• Sizable minority of women report an overall negative body image
• 36% report wholesale body dissatisfaction on BASS
• 48% report unfavourable view of their body on AE
• 49% report concerns about being overweight
BASS BreakdownPhysical Area % Dissatisfied % Dissatisfied/Neutral
Face 11.7 30.4
Height 13.4 30.2
Hair 16.3 28.0
Upper-torso 25.1 47.3
Muscle tone 36.9 63.9
Weight 46.0 63.3
Lower-torso 47.4 64.2
Mid-torso 51.0 69.8
Effect of Age and Race
• Age-cohort differences significant on AE scale, but not BASS or OP
• 18-24 years have more favourable body image than the four older groups (25-34, 35-44, 45-54, 55-70)
• Black women had more favourable body image than Anglo and Hispanic women
Disturbing Trend
• Nearly 50% of the women surveyed reported globally negative evaluations of looks and concerns about becoming overweight
• Over 33% expressed body-image discontent
• Much worse than the 1985 survey– 30% --> 48% unfavourable MB SRQ score
Cash, Ancis, & Strachan (1997)
• Learning?
• Cultural forces influence body image
• Jackson (1992)– Across lifespan, women have poorer body
image than men
• Gender attitudes
• Ideologies
Cultural Norms
• Argued that cultural norms and expectations encourage women & girls to focus attention on their physical appearance– Femininity ideals
• Role of values, attitudes, gender identities?
• Do nontraditional gender attitudes lead to more positive body image?
“Types”
• Traditional (T)
• Feminist identity (F)
• Hypotheses– T associated with greater body-image
investment– T has more negative body-image evaluations
and affect
Study
• 122 female undergraduate students
• Questionnaire
• Gender Attitude Inventory (GAI)– Gender stereotypes
– Sexual relationships
– Societal organizations
• Male-Female Relations Questionnaire (MFRQ)– Social interaction with men
– Male preference
• Feminist Identity Development Scale (FIDS)– Five stages of feminist
development
• Multidimensional Body-Self Relations Questionnaire (MB SRQ)
Results
• Did not support idea that development of feminist identity or endorsement of egalitarian social identity --> more positive body image
• Also, traditional identity is not responsible for controlling body image issues
Waist-to-Hip Ratio
• Not developed by Singh• Measure going back into early-mid 20th century
for medical purposes• Reflects distribution of fat between upper and
lower body and relative amount of intra- vs. extra-abdominal fat
• Measure waist at narrowest point b/t ribs and iliac crest and hip at greatest protrusion of buttocks circumferences
Cutting to the Chase
• Basically, Singh’s early work supported a:
• Male preference for women with WHRs around 0.7
• Female recognition of male preference
0.74 0.70 0.68 0.71
WHRat
theOscars(a few years back)
Amazon overcoming a Greek (c. 350 BC)
Venus (Capitoline type)(Rome copy of Greek, c. 360 BC)
Aphrodite bathing (Roman, c. 150 AD)
The Three Graces(by Antonio Canova, 1815-17)
Female/Male Differences
• Differences in post-puberty fat deposition patterns
• Females: add fat to gluteofemoral region
• Males: lose fat from gluteofemoral region and add to central abdomen and upper body (shoulders, neck)
WHR Issues
• Age
• Health
• Reproductive fitness, fecundity
• All factor into potential adaptation for mate selection
Sex Hormonal Role
• Testosterone: stimulates fat deposits to abdomen and inhibits deposits to gluteofemoral regions
• Estrogens: inhibit fat deposits in abdomen and maximally stimulate deposits to gluteofemoral region (and other regions, too)
Android and Gynoid
• Body shapes• Healthy body weight
range• Highly different from
children and elderly• Altering sex hormones
alters fat distributions and body shape
Image modified from Pioneer Plaqueshttp://www.nd.edu/~jmontgom/ti/GraphicArchive/Scans/Original%20Files/Pictograph/PioneerPlaque.jpg
Males: High Testosterone
Charles Atlas Leo Robert Dave Draper
And… Really High Testosterone
El Shahat MabroukLee Haney Dorian Yates Ronnie Coleman
Female: Low Estrogens, High Testosterone
(Ms. Olympia 2003)
Children
http://www.tootsiesdancewear.com/members/547048/uploaded/132C_4.jpg
• Pre-sex hormone• Fat deposition fairly
similar between sexes• Can be difficult to
distinguish by fat deposit form
• Clear difference between pre- and post-puberty shapes
Weight
• Anorexia to obesity: both interfere with body shape judgments
http://www.humanillnesses.com/original/images/hdc_0001_0002_0_img0094.jpg
Elderly
• Circulating sex hormones drop
• Females add fat deposits to abdomen
• Male muscle mass drops, reducing android shape; fat depositions generally follow earlier pattern
• Loss in sex differentiation based on fat deposition
Health
• Variety of heritable issues linked to fat deposition patterns
• Polycystic ovarian syndrome, advanced cirrhosis, hypogonadism, Klinefelter syndrome, etc.
• Obesity itself has numerous complications: cardiac issues, diabetes, stroke, hypertension, etc.
Reproductive Status
• Obviously, linked to issues of age
• Hormone levels (lutenizing hormone, follicle-stimulating hormone, sex steroids)
• Stored energy levels; pregnancy and childrearing is going to be expensive
• Concealed ovulation and current fecundity status
WHR Speculation:Pregnant or Plump?(Remember this?)
Pregnancy
• Obvious WHR effect
• Relatively early indicator of pregnancy
http://www.virtualmedicalcentre.com/uploads/VMC/DiseaseImages/2487_pregnancy_ext_440.jpg
Singh (1993)
• Manipulated WHR to change perceived attractiveness
• If WHR preference is adaptation, should see fairly consistent outcomes
• Attractiveness, healthiness, reproductive capacity
Earlier Work on Idealized Figure
• Women guess males prefer thin female
• Males actually prefer not very thin
• Studies utilized body size (thin vs. fat), not shape (i.e., fat distribution)
• Singh’s work utilized both size and shape
Stimuli
• Underweight, normal, overweight
• 0.7 to 1.0 WHRs
Stimuli
Results: Young Subjects
Results
• Generally, similar male and female patterns in rankings
• Used both WHR and body weight to rank• Within weight category, subjects systematically
used WHR to infer all attributes• Overall, higher ratings for normal weight than
under- or overweight figures, and for 0.7 WHR across weight categories
Results: Older Subjects (30-86)
Results
• Again, general agreement between sexes
• Unlike younger men, older men didn’t rank U7 as attractive, healthy, or reproductive
Youthfulness
• Lack of association between youthfulness and reproductive capacity
• In particular, underweights ranked high for youthfulness, but low for reproductive capacity
To Young to Reproduce?
• Age estimates– Underweights: 17-19– Normals: 23-26– Overweights: 31-33
• Not because underweights are being judged pre-pubescent
• Body weight, more than WHR, used for age estimates
Honest Signals
• Signals = traits
• Honest if signal correlates with/reliably predicts something useful to receiver of signal
• Difficult to fake
• Too much dishonest signaling will disrupt the system
WHR as Signal
• Singh’s work shows males and females attend to WHR
• Utilized for a number of determinations
• Health, attractiveness, and particular WHRs closely linked
• Hamilton & Zuk (1982): sexual selection for signals of good health
Uniquely Human
• Gluteofemoral fat deposits
• No sexual dimorphism for fat distribution
• Development no more than 5-6 mya, likely much more recently
http://s.buzzfed.com/static/imagebuzz/terminal01/2009/4/20/11/hairless-chimpanzee-10348-1240240236-2.jpg
http://blog.theavclub.tv/wp-content/uploads/2007/05/chimpanzee.jpg
http://www.mccullagh.org/db9/10d-17/vervet-monkey.jpg
Bipedalism and Brain Size• Bipedal Australopithecines 4.2-3.9 mya
• Brain size increases ~2.7 mya
• Newborn ape’s brain about 200 cc, roughly half that of an adult’s
• Newborn human’s brain about 450 cc, roughly a third the size of an adult’s
• Brain of 675 cc would make human head too large to birth
Ancestral Growth Patterns
• Ancestors left apelike growth when adult brain passed about 770 cc– Beyond this, brain would have to more than double from birth– Beginning of helplessness in infants
• H. habilis, 800 cc brain; H. erectus, 900 cc brain• Late H. erectus’ (post 800 k) tooth growth pattern like
modern humans (and Neanderthals)• Puts birthing and childrearing issues becoming significant
somewhere around 1.7-1.0 mya
Fat Stores• Storage fat
– Depends on nutritional status; subcutaneous deposits– 8-10% total body weight, both males and females
• Essential fat– Includes gender-specific fat, bone marrow, deep fat
stores, CNS– 14% of female total body weight; only 2-4% in males– Not utilized for short-term food shortage– “Reproductive fat” for females– Gluteofemoral fat stores primarily used in late
pregnancy and lactation
Reproductive Capability
• Gluteofemoral fat stores
• Energy for gestation and lactation
• Proper infant brain development requires lipids and lactose
• Differential reproductive success
WHR• Good indicator of general
health as well as reproductive capacity
• Selection favoured males who picked females with stored “reproductive” calories, not general obesity– Studies show difficulties in
conception with higher WHRs
Venus of Dolni Vestonice(29,000-25,000 BCE)
en.wikipedia.org/wiki/File:Venus_of_Dolni_Vestonice.png
Feedback
• Men favoured gynoid fat distribution• These women’s reproductive success
increased the genes for the gynoid form in the gene pool
• Sexy daughters and sons with fathers’ preference
• Reasonable argument for WHR as honest signal