Study explores accuracy of body weight perception and obesity in Chinese Americans

May 28 2015

Worldwide, obesity is becoming more prevalent. According to The World Health Organization, worldwide obesity has nearly doubled since 1980, and in 2008 25% of adults aged 20 and over were overweight, and another 11% were obese. Obesity has been identified as a major source of unsustainable health costs and numerous adverse outcomes, including morbidity and mortality due to hypertension, type 2 diabetes, cardiovascular diseases and certain types of cancer.

Accuracy of body weight perception is an individual's perception of their body weight (normal weight, overweight, or underweight) in comparison to their actual body weight. Research has shown accuracy of body weight perception to predict life style behaviors, efforts to lose weight and even medical visits.

Chinese Americans make up the largest subgroup of Asian Americans and represent 4% of the total U.S. population. However, when compared to their counterparts in China, Chinese Americans have an increased risk for obesity due to immigration and environmental changes they face in the United States. A recent study published in Obesity Research & Clinical Practice by researchers affiliated with NYU's College of Nursing (NYUCN) is the first to examine the accuracy of body weight perception in Chinese Americans.

The study, "Accuracy of body weight perception and obesity among Chinese Americans," explored the accuracy of body weight perception and its impact on obesity in Chinese Americans by examining the associations between 162 participants' accuracy of body weight perception in relation to obesity-related physical characteristics and indicators. To do so, researchers gauged participants' demographic information, and anthropometric measures in addition to weight, such as height, waist circumference (WC), hip circumference (HC) and body mass index (BMI).

"Among the 162 Chinese Americans recruited to this study, we found that 32 had underestimated their weight, 20 had overestimated, and 110 had accurate perceptions of their weight," said Mei R. Fu, PhD, RN, ACNS-BC, FAAN, associate professor of Chronic Disease Management at NYUCN.

Significant differences were found among participants in three groups of different accuracy of body weight perception in terms of gender, age, and education years. In the underestimation group, men were 2.34 times more likely to believe they were underweight, compared to women. In the overestimation group, women were 3.59 times more likely than men to think they were overweight. Participants in the overestimation group were on average, 14.7 years younger than participants in the underestimation group, and 13.6 years younger than participants who had accurately perceived their weight. On average, participants who had underestimated their weight had 3.2 fewer year of education, when compared to those who had overestimated their weight.

The results from this study also found accuracy of body weight perception significantly predicted waist circumference, hip circumference, weight to height ratio, BMI and weight, even after controlling for all demographic factors. Participants in the consistent estimation group and underestimation group had similar waist and hip circumferences and weight/height ratios, but much higher than the participants in the overestimation group. With regards to obesity-related physical characteristics and diseases, accuracy of body weight perception was found to not be related with HbA1C, hypertension and heart disease.

As the first to examine the accuracy of body weight perception in Chinese Americans, this study identified that approximately one-third of Chinese Americans incorrectly perceived their body weight. Having found that accuracy of bodyweight perception was associated with several demographic factors, this study lays a good foundation for future possible intervention studies for obesity management in Chinese Americans. The findings of this study also suggest that such intervention studies should address gender difference, target older subjects, and focus on educating Chinese Americans on normal values for waist and hip circumference and HbA1C.