Dimensional analysis of the concept of obesity

May 3 2006

Health professionals need to use more than tape measures and scales to define and tackle obesity, according to a paper in the latest Journal of Advanced Nursing.

A research review carried out by Maryanne Davidson from Yale University, USA, has discovered that many women don't make the link between high weight and poor health and that culture plays a big role in how positively they see themselves.

She reviewed key papers published over a 10-year period to see how health professionals and Black and White American women define obesity and to identify differences in attitudes.

This revealed that while health professionals used quantitative methods, such as Body Mass Index measurements based on the height to weight ratio, women are more likely to base their ideal weight on cultural criteria.

"My review revealed that Black American participants defined obesity in positive terms, relating it to attractiveness, sexual desirability, body image, strength or goodness, self esteem and social acceptability" says Davidson. "In addition they didn't view obesity as cause for concern when it came to their health."

White Americans, on the other hand, expressed completely the opposite view.

"They defined obesity in negative terms, describing it as unattractive, not socially desirable, associated with negative body image and decreased self-esteem and being socially unacceptable.

"But when it came to the links between body weight and health, this group was much more likely to voice mixed views, with some expressing concern and others feeling that weight wasn't a health issue.

Davidson also discovered variations in how health professionals define obesity.

"Although most of them use the Body Mass Index to actually measure obesity, we found different views about what level of BMI constitutes normal weight and what level indicates obesity" she says.

"I'm glad to say that that situation is changing and there is a move towards standardised measurement of what is obese and what is overweight. For example the International Obesity Task Force is helping to address the need for a global objective measurement based on BMI."

The findings provide a real challenge for healthcare professions.

"These differences could pose substantial threats to communication and understanding between healthcare providers and their patients. That's why it is so important that obesity is approached in a culturally sensitive way, rather than just using quantitative measures like the Body Mass Index."

People have been obsessed with their weight since records began, says Davidson, who points out that the Spartans reportedly ostracised a man for being too fat and Socrates danced every day to keep his weight within reason!

The concept of obesity in the United States appears to date back to the insurance industry, which published tables in 1912 defining average and acceptable weights for American adults.

These were updated in 1959 with average weight being replaced by ideal weight and obesity being defined as 20 per cent above this figure. That change put 40 per cent of American women in the seriously overweight category.

"Obesity is a major issue for health professionals as it is emerging as a worldwide healthcare epidemic" says Davidson. "The World Health Organization estimates that there are at least 300 million obese people worldwide and a further one billion who are overweight.

"It's also clearly a cultural issue, as rates range from below five per cent in China, Japan and some African nations to more than 75 per cent in urban Samoa.

"Recent data also suggests that 54 per cent of adult Americans are overweight and that women of all cultures are particularly affected.

"Key health issues related to obesity include diabetes, high blood pressure and cholesterol, asthma and some cancers.

"That's why it's imperative that researchers and healthcare providers understand how people from different cultures view obesity.

"This will help them to promote key messages about the health risks associated with excess weight in a culturally sensitive way."