Waist-hip ratio - AbsoluteAstronomy.com

Waist–hip ratio or waist-to-hip ratio (WHR) is the ratio

Ratio

In mathematics, a ratio is a relationship between two numbers of the same kind , usually expressed as "a to b" or a:b, sometimes expressed arithmetically as a dimensionless quotient of the two which explicitly indicates how many times the first number contains the second In mathematics, a ratio is...

of the circumference of the waist

Waist

The waist is the part of the abdomen between the rib cage and hips. On proportionate people, the waist is the narrowest part of the torso....

to that of the hips.

WHO STEPS

Accoding to WHO STEPS the waist circumference should be measured at the midpoint between the lower margin of the
least palpable rib and the top of the iliac crest, using a stretch‐resistant tape that provides a
constant 100 g tension. Hip circumference should be measured around the widest portion
of the buttocks, with the tape parallel to the floor.

For both measurements, the subject should stand with feet close together, arms at the side
and body weight evenly distributed, and should wear little clothing. The subject should be
relaxed, and the measurements should be taken at the end of a normal expiration. Each
measurement should be repeated twice; if the measurements are within 1 cm of one
another, the average should be calculated. If the difference between the two
measurements exceeds 1 cm, the two measurements should be repeated.

Practical measurement

Practically, however, the waist is more conveniently measured simply at the smallest circumference of the natural waist, usually just above the belly button, and the hip circumference may likewise be measured at its widest part of the buttocks or hip. Also, in case the waist is convex rather than concave, such as is the case in pregnancy and obesity, the waist may be measured at a horizontal level 1 inch above the navel.

Indicator of health

The WHR has been used as an indicator or measure of the health of a person, and the risk of developing serious health conditions. Research shows that people with "apple-shaped" bodies (with more weight around the waist) face more health risks than those with "pear-shaped" bodies who carry more weight around the hips.

WHR is used as a measurement of obesity

Obesity

Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...

, which in turn is a possible indicator of other more serious health conditions.

WHO STEPS states that abdominal obesity is defined as waist–hip ratio above 0.90 for males and above 0.85 for females, or a BMI above 30.0.. The use of the word "above" here makes the meaning of this statement unclear. A higher WHR would be a smaller number eg. 0.6 is a higher ratio than 0.9. One would think that a higher ratio (above ?)i.e. more difference between waist and hip would be less obese. A lower ratio i.e. > 0.9 would mean that the hips and waist are closer to the same size.

The National Institute of Diabetes, Digestive and Kidney Diseases (NIDDK) states that women with waist-to-hip ratios of more than 0.8 are at increased health risk because of their fat distribution. And that men with waist-to-hip ratios of more than 1.0 are at increased health risk because of their fat distribution.. The use of the word "more" in the above sentence confuses the meaning as a ratio of "more than 0.8" is a smaller number than 0.8. This would mean that there is more difference between waist and hip measurement which is unlikely to be an "increased health risk". The increased health risk is where the waist and hips are a more similar measurement meaning that the number is higher or closer to unity i.e. the number is higher or a lesser (reduced) ratio.

A WHR of 0.7 for women and 0.9 for men have been shown to correlate strongly with general health

Health

Health is the level of functional or metabolic efficiency of a living being. In humans, it is the general condition of a person's mind, body and spirit, usually meaning to be free from illness, injury or pain...

and fertility

Fertility

Fertility is the natural capability of producing offsprings. As a measure, "fertility rate" is the number of children born per couple, person or population. Fertility differs from fecundity, which is defined as the potential for reproduction...

. Women within the 0.7 range have optimal levels of estrogen

Estrogen

Estrogens , oestrogens , or œstrogens, are a group of compounds named for their importance in the estrous cycle of humans and other animals. They are the primary female sex hormones. Natural estrogens are steroid hormones, while some synthetic ones are non-steroidal...

and are less susceptible to major diseases such as diabetes, cardiovascular disorders and ovarian cancers (tenuous). Men with WHRs around 0.9, similarly, have been shown to be more healthy and fertile with less prostate cancer

Prostate cancer

Prostate cancer is a form of cancer that develops in the prostate, a gland in the male reproductive system. Most prostate cancers are slow growing; however, there are cases of aggressive prostate cancers. The cancer cells may metastasize from the prostate to other parts of the body, particularly...

and testicular cancer

Testicular cancer

Testicular cancer is cancer that develops in the testicles, a part of the male reproductive system.In the United States, between 7,500 and 8,000 diagnoses of testicular cancer are made each year. In the UK, approximately 2,000 men are diagnosed each year. Over his lifetime, a man's risk of...

.

WHR has been found to be a more efficient predictor of mortality in older people than waist circumference or body mass index

Body mass index

The body mass index , or Quetelet index, is a heuristic proxy for human body fat based on an individual's weight and height. BMI does not actually measure the percentage of body fat. It was invented between 1830 and 1850 by the Belgian polymath Adolphe Quetelet during the course of developing...

(BMI). If obesity is redefined using WHR instead of BMI, the proportion of people categorized as at risk of heart attack worldwide increases threefold. The body fat percentage

Body fat percentage

A person's body mass percentage is the total weight of the person's fat divided by the person's weight and consists of essential body fat and storage body fat. Essential body fat is necessary to maintain life and reproductive functions. The percentage of essential body fat for women is greater than...

is considered to be an even more accurate measure of relative weight. Of these three measurements, only the waist-hip ratio takes account of the differences in body structure. Hence, it is possible for two women to have vastly different body mass indices but the same waist-hip ratio, or to have the same body mass index but vastly different waist-hip ratios.

Even in ancient civilizations globally, female representations are most often in the 0.6-0.7 range for WHR, suggesting a preference towards lower WHR. The meaning of this is confused by the word "lower". A "lower" WHR is a bigger number (closer to 1) meaning that the waist and hips are closer to the same measurement which doesn't make sense in the above sentence.

Other studies have found that waist circumference, not WHR, to be a good indicator of cardiovascular risk factors, body fat distribution, and hypertension in type 2 diabetes.

Measure of attractiveness

The concept and significance of WHR as an indicator of attractiveness was first theorized by evolutionary psychologist

Evolutionary psychology

Evolutionary psychology is an approach in the social and natural sciences that examines psychological traits such as memory, perception, and language from a modern evolutionary perspective. It seeks to identify which human psychological traits are evolved adaptations, that is, the functional...

Devendra Singh

Devendra Singh was a professor of Psychology at the University of Texas, known largely for his research regarding the evolutionary significance of human attraction.-Biography:...

at the University of Texas at Austin

University of Texas at Austin

The University of Texas at Austin is a state research university located in Austin, Texas, USA, and is the flagship institution of the The University of Texas System. Founded in 1883, its campus is located approximately from the Texas State Capitol in Austin...

in 1993. Singh argued that the WHR was a more consistent estrogen marker than the Bust-waist ratio

BWH

BWH is an abbreviation of bust, waist, and hip measurement. Also informally called vital statistics, these measurements are a common method of specifying body proportions for the purpose of fitting clothes. It is also often used in women's personal ads or Internet profiles to indicate their...

(BWR) studied at King's College, London by Dr. Glenn Wilson

Glenn Wilson (psychologist)

Glenn Daniel Wilson is a psychologist best known for his work on attitude and personality measurement, sexual attraction, deviation and dysfunction, partner compatibility, and psychology applied to performing arts.In 2001, Wilson was ranked among the 10 most frequently cited British psychologists...

in the 1970s.

Some researchers have found that the waist-hip ratio (WHR) is a significant measure of female attractiveness. Women with a 0.7 WHR are usually rated as more attractive by men from Indo-European

Indo-European

Indo-European may refer to:* Indo-European languages** Aryan race, a 19th century and early 20th century term for those peoples who are the native speakers of Indo-European languages...

cultures. Beauty icons such as Marilyn Monroe

Marilyn Monroe

Marilyn Monroe was an American actress, singer, model and showgirl who became a major sex symbol, starring in a number of commercially successful motion pictures during the 1950s....

, Jayne Mansfield

Jayne Mansfield

Jayne Mansfield was an American actress working both in Hollywood and on the Broadway theatre...

, Salma Hayek

Salma Hayek

Salma Valgarma Hayek Jiménez de Pinault is a Mexican film actress, director and producer. She received an Oscar nomination for Best Actress for her role as Frida Kahlo in the film Frida.-Early life:...

and Sophia Loren

Sophia Loren

Sophia Loren, OMRI is an Italian actress.In 1962, Loren won the Academy Award for Best Actress for her role in Two Women, along with 21 awards, becoming the first actress to win an Academy Award for a non-English-speaking performance...

typically have ratios close to 0.6, even though they have different weights and heights. In other cultures, preferences appear to vary according to some studies, ranging from 0.6 in China, to 0.8 or 0.9 in parts of South America and Africa, and divergent preferences based on ethnicity, rather than nationality, have also been noted.

It appears that men are more influenced by female waist

Waist

The waist is the part of the abdomen between the rib cage and hips. On proportionate people, the waist is the narrowest part of the torso....

-size than hip-size:
To enhance their perceived attractiveness, some women may artificially alter their apparent WHR. The methods include the use of a corset

Corset

A corset is a garment worn to hold and shape the torso into a desired shape for aesthetic or medical purposes...

to reduce the waist size and hip and buttock padding

Hip and buttock padding

Hip and buttock padding is used by some transgender people including transsexuals and cross-dressers. It is used to increase the apparent size of the hips and buttocks to resemble those of a female...

to increase the apparent size of the hips and buttocks. In an earlier attempt to quantify attractiveness, corset

Corset

A corset is a garment worn to hold and shape the torso into a desired shape for aesthetic or medical purposes...

and girdle

Girdle

A girdle is a garment that encircles the lower torso, perhaps extending below the hips, and worn often for support. The word girdle originally meant a belt. In modern English, the term girdle is most commonly used for a form of women's foundation wear that replaced the corset in popularity...

manufacturers of the 20th century used a calculation called hip spring (or hip-spring or hipspring). Hip spring is calculated by subtracting the waist measurement from the hip measurement. However, this calculation fell into disuse because it is a poor indicator of attractiveness; for example, a hip spring of 10 inches (25.4 cm) would likely be considered quite attractive for an average-sized adult woman, but a child or petite woman with the same number would more likely be seen as malnourished.

Cognitive Ability

Using data from the U.S. National Center for Health Statistics, William Lassek at the University of Pittsburgh in Pennsylvania and Steven Gaulin of the University of California, Santa Barbara, found a child's performance in cognitive tests correlated to their mother's waist-hip ratio, a proxy for how much fat she stores on her hips.

Children whose mothers had wide hips and a low waist-hip ratio scored highest, leading Lassek and Gaulin to suggest that fetuses benefit from hip fat, which contains long chain polyunsaturated fatty acids, critical for the development of the fetus's brain. In addition, evidence suggests that children of low-WHR teens were protected from the cognitive deficits often associated with teen birth.
Consistent with cognitive epidemiological

Cognitive epidemiology

Cognitive epidemiology is a field of research that examines the associations between intelligence test scores and health, more specifically morbidity and mortality. Typically, test scores are obtained at an early age, and compared to later morbidity and mortality...

data, numerous studies confirm that obesity is associated with cognitive deficits. Whether obesity causes cognitive deficits, or vice versa is unclear at present.

External links

Waist-hip ratio should replace body mass index as indicator of mortality risk in older people EurekAlert August 8, 2006
Genes for 'pear shape' found, NHS Choices, October 11, 2010