FRIDAY, Dec. 2, 2011 (HealthDay News) -- Racial and ethnic differences in diet, exercise and weight may be due to differences in socioeconomic status, a new U.S. study suggests.
The researchers found that people with a lower socioeconomic status are more likely to be overweight than those with higher socioeconomic status, regardless of racial or ethnic background. They also found that levels of nutritional knowledge and health awareness weren't associated with significant racial differences in diet and weight.
In the study, published in the December issue of the Journal of the American Dietetic Association, Johns Hopkins researchers analyzed nationally representative data collected from over 4,300 people who took part in the U.S. Department of Agriculture's Continuing Survey of Individual Food Intakes.
The participants had completed the Diet and Health Knowledge Survey, which asked questions related to diet and health. Socioeconomic status was assessed using education and household income.
In general, blacks had higher body mass index (BMI, a measurement that takes into account height and weight), scored lower on the USDA's healthy eating index and got less exercise than whites. Hispanics scored higher on the health index than whites, the study authors noted.
After they controlled for socioeconomic status, the researchers found that differences in the health index between whites and blacks become smaller, while differences between whites and Hispanics became greater.
"Our study shows several important findings that could help enhance the understanding of the complex factors that affect disparities in diet, exercise, and obesity across ethnic and [socioeconomic status] groups," Dr. Youfa Wang, director of the Johns Hopkins Global Center for Childhood Obesity and an associate professor of International Health and Epidemiology, said in a journal news release.
"Different from what we expected, few of the racial/ethnic differences in diet, exercise and weight status were explained by health- and nutrition-related psychosocial factors. But [socioeconomic status] explained a considerable portion of the disparities," he noted.
"The underlying causes of ethnic disparities in eating, exercise and obesity in the United States are complicated," Wang added. "More well-designed studies with vigorous and comprehensive assessment of related factors are needed to help advance understanding."
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