Waist to Hip ratio

I'm overweight. BMI and Waist to hip ratio both indicate that fact.

At 5'7.5" and 12st 11 1bs or 179 pounds at 30th December 2006 (was 13st 8lbs a few months ago!) my BMI is 27.6.

Methods for actually measuring body fat percentage are preferable to BMI for measuring healthy body size. Mayo Clinic researchers say the BMI doesn't accurately predict risk of cardiovascular death because it doesn't distinguish between muscle and fat. They say a better measure may be your Waist-hip ratio (wikipedia). The evidences is that in an analysis at Mayo Clinic led by Lopez-Jiminez of 40 studies involving 250,000 people, heart patients with normal BMIs were at higher risk of death from cardiovascular disease than people whose BMIs put them in the "obese" range. The ones in the study who had the highest death rates were people who weighed the least; in other words, they had the lowest BMIs (reference citation required).

My Waist-hip ratio is 104cm/99cm (41"/39") or 1.05, Sharon's is 34"/41" (86cm/104") or 0.83.

According to NICE NHS booklet (December 2006): target for men is <94cm>

Source: NICE Guideline Booklet

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. Men with WHRs around 0.9, are more healthy and fertile with less prostate and testicular cancer.

WHR is considered to be factor in a person's attractiveness. Women with a 0.7 WHR are often rated as more attractive by men regardless of culture, race, religion or ethnicity. Such diverse beauty icons as Marilyn Monroe, Twiggy, Sophia Loren, Kate Moss, Salma Hayek and even the Venus de Milo all have ratios around 0.7, even though they have significantly different weights. Congruent with an evolutionary perspective, evidence suggests that humans use subtle biological cues, such as WHR, to indicate mate potential and fertility.

Abdominal Obesity in INTERHEART study

This study found that BMI showed a modest and graded association with risk of Myocardial Infarction MI (Heart Attack). Waist and hip circumferences were both highly significantly associated with risk of MI. Waist-to-hip ratio was a better measure of risk than waist circumference alone.

Obesity and CVD: Biologic Mechanisms

The biologic mechanisms underlying the relation between obesity and cardiovascular risk are unclear. The waist-to-hip ratio is a simple measure for visceral obesity, and visceral adiposity is a manifestation of the metabolic abnormalities that underlie risk of future CVD events. It may be that the ratio of fat to muscle (sarcopenic adiposity) can be a measure of risk of CVD, which is best estimated by waist-to-hip ratio.

Visceral adiposity is the fat that is integrated within the abdominal organs, as opposed to subcutaneous fat, as measured by the "skin-fold" test.

These results suggest that it is not how much fat a patient has, but where it is stored that contributes to overall cardiovascular risk, insulin resistance, and glucose tolerance. It means that waist and hip circumferences provides a predictive power greater than that provided by BMI for estimating the risk of MI.

With the redefinition of abdominal obesity based on waist-to-hip ratio instead of BMI, the estimated risk of MI attributable to obesity was higher than previously assumed and the risk of MI rose progressively with increasing values for waist-to-hip ratios with no evidence of a threshold.

The global burden of obesity has been substantially underestimated by the reliance on BMI.

• INTERHEART estimated
  
• 63% of heart attacks were due to abdominal obesity indicated by a high waist to hip ratio (for men >0.95, for women >0.85).
  
• Those with abdominal obesity were at over twice the risk of a heart attack compared to those without.
  
• Abdominal obesity was a much more significant risk factor for heart attack than BMI.
• men (33%) and women (30%) had a high waist to hip ratio.
• benefits may accrue by redistribution of the body's fat stores to the hips or by increasing muscle mass.