Waist-hip ratio

The waist-hip ratio in women is often considered a key feature in physical attractiveness. Measured directly from this image, the frontal WHR of the model in this image is approximately 0.69.

Men generally have much less pronounced hips, relative to waist size.

Waist-hip ratio or Waist-to-hip ratio (WHR) is the ratio of the circumference of the waist to that of the hips. It is calculated by measuring the smaller circumference of the natural waist, usually just above the belly button, and dividing by the hip circumference at its widest part of the buttocks or hip. The ratio is applied both to women and men.

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. (See female body shapes)

WHR is used as a measurement of obesity, which in turn is a possible indicator of other more serious health conditions.

A WHR of 0.7 for women and 0.9 for men have been shown to correlate strongly with general health and fertility. Women within the 0.7 range have optimal levels of estrogen and are less susceptible to major diseases such as diabetes, cardiovascular disorders and ovarian cancers.^[1] Men with WHRs around 0.9, similarly, have been shown to be more healthy and fertile with less prostate cancer and testicular cancer.^[2] Studies show that 80 percent of women over the age of 18 have a WHR of at least 0.9^{[citation needed]}. This is a 40 percent increase since 2002, and it keeps increasing.

WHR has been found to be a more efficient predictor of mortality in older people than waist circumference or body mass index (BMI)^[3] If obesity is redefined using WHR instead of BMI, the proportion of people categorized as at risk of heart attack worldwide increases threefold.^[4] The body fat percentage 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.

The ideal ratio for women is considered to be about 0.7.^[5]

Other studies have found that waist circumference, not WHR, to be a good indicator of cardiovascular risk factors,^[6] body fat distribution,^[7] and hypertension in type 2 diabetes.^[8]

Measure of attractiveness

The concept and significance of WHR as an indicator of attractiveness was first theorized by evolutionary psychologist Dr. Devendra Singh at the University of Texas at Austin in 1993.^[9][10] Singh argued that the WHR was a more consistent oestrogen marker than the BHR studied at King's College, London by Dr Glenn Wilson in the 1970s.^[11][12]

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 European cultures.^[13] Such diverse beauty icons as Audrey Hepburn, Marilyn Monroe, Sophia Loren and even the Venus de Milo all have or had ratios close to 0.7, even though they all have different weights and heights. In other cultures, preferences appear to vary according to some studies,^[14] ranging from 0.6 in China,^[15] to 0.8 or 0.9 in parts of South America and Africa,^[16][17][18] and divergent preferences based on ethnicity, rather than nationality, have also been noted.^[19][20]

Note: In the studies referenced above, only frontal WHR preferences differed significantly among racial and cultural groups. When actual (circumferential) measurements were made, the preferred WHR tended toward the expected value of 0.7 universally. The apparent differences are most likely due to the different body fat storage patterns in different population groups. For example, women of African descent tend to store their fat in their buttocks more than women of other groups. Therefore, their WHR as viewed from the front may appear to be much greater than when viewed from the side. The inverse may be true of women of East Asian ancestry. Therefore, African men appear to be more likely to value a woman's small WHR in profile and Asian men may tend to place more value on an exaggerated frontal WHR compared to European men.

It appears that men are more influenced by female waist-size than hip-size :

"Hip size indicates pelvic size and the amount of additional fat storage that can be used as a source of energy. Waist size conveys information such as current reproductive status or health status ... in westernized societies with no risk of seasonal lack of food, the waist, conveying information about fecundity and health status, will be more important than hip size for assessing a female's attractiveness."

—Journal of Biological Psychology, ^[21]

Another reason that men may favour a lower waist-hip ratio is that in stressful situations, women's hormones may make their WHR higher; the same hormones that act to make a woman physically stronger also make her WHR higher.^[22]

To enhance their perception of attractiveness, some women may artificially alter their apparent WHR. The methods include the use of a corset to reduce the waist size and hip and buttock padding to increase the apparent size of the hips and buttocks. In an earlier attempt to quantify attractiveness, corset and girdle manufacturers of the 20th century used a calculation called hip spring^[23] (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 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.

Intelligence

While the study is still being reviewed, there is a moderate correlation between WHR and intelligence of offspring. 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 cognition tests was linked to their mother's waist-hip ratio, a proxy for how much fat she stores on her hips.^[24]

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 that contains polyunsaturated fatty acids critical for the development of the fetus's brain.^[24]

See also

• Body fat percentage
• Body Volume Index
• Body mass index
• Sagittal Abdominal Diameter (SAD)
• Central obesity
• Physical attractiveness
• Sexual attraction

References

External links

• Waist-hip ratio should replace body mass index as indicator of mortality risk in older people EurekAlert August 8, 2006
• Waist-to-hip ratio
• Calculate your Waist-Hip Ratio and six other parameters
• WHR calculator - Calculate your waist to hip ratio and determine your overall health risk.