American Heart Association: 81.8% of obese women underestimate their weight

Overweight and obese mothers and their children think they weigh less than their actual weight, according to research reported at the American Heart Association's Nutrition, Physical Activity and Metabolism/Cardiovascular Disease Epidemiology and Prevention 2011 Scientific Sessions.  

In the study of women and children in an urban, predominantly Hispanic population, most normal weight women and children in the study correctly estimated their body weight, but most obese women and children underestimated theirs.

"Obesity is a well-known risk factor for the development of many diseases, including heart disease and diabetes," said Nicole E Dumas, M.D., lead author and an internal medicine resident at Columbia University Medical Center in New York City. Dumas and colleagues surveyed women and their pre-adolescent children attending an urban, primary care center in New York City. They asked the subjects about their age, income, heart disease risk factors, and perceptions of their body size using silhouette images that corresponded to specific body mass index (BMI) types — for example, underweight, normal and overweight.  

The researchers also recorded participants' height, weight and BMI, which is a measurement of body weight based on height. A BMI of 25-29 is overweight, and a BMI over 30 is obese.

The researchers found:

• 65.8 percent of the mothers surveyed were overweight or obese.
• 38.9 percent of children surveyed were overweight or obese.
• 81.8 percent of obese women underestimated their weight compared to 42.5 percent of overweight and 13.2 percent of normal weight women; similarly, 86 percent of overweight or obese children underestimated their weight compared to 15 percent of normal weight children.
• Of mothers with overweight or obese children, almost half (47.5 percent) thought their children were of normal weight.
• Children selected larger body images than those chosen by their mothers to describe an  "ideal" or "healthy" body image for a woman.
• 41.4 percent of the children in the study thought their moms should lose weight.

"These findings imply that not only is obesity prevalent in urban America, but that those most affected by it are either unaware or underestimate their true weight," she said. "In addition, obesity has become an acceptable norm in some families. Strategies to overcome the obesity epidemic will need to address this barrier to weight loss."

Future research should include interventions that study the effect of increased accuracy of body image perception on weight loss among families.