A UC Riverside study highlights major health problems affecting historically ignored racial groups.

Some of the smallest and historically neglected racial groups in the United States experience far more obesity, diabetes, and other health conditions than non-Hispanic white adults, a study by researchers at the University of California, Riverside has found.

Using data for nearly 185,000 adults from the California Health Interview Survey (CHIS), the study reports that multiracial, Native Hawaiian and Other Pacific Islander (NHOPI), and American Indian and Alaskan Native (AIAN) adults in California endure large obesity and diabetes-related health disparities that exceed those experienced by non-Hispanic white adults, and, in many cases, other racial minorities such as African Americans and Hispanics.

The study, published in the journal Obesity, is among the first large-scale, population-based investigations to explore the presence of major health disparities affecting multiracial, NHOPI and AIAN adults. Drawing from years of statewide California data, it is also one of the most accurate estimates to date of obesity-related health disparities affecting these understudied groups. Most health data only code participants into standard non-Hispanic white, Hispanic, African American and Asian American racial categories, while excluding multiracial, NHOPI and AIAN individuals from analysis. For example, almost all health data about Pacific Islanders are grouped with Asian Americans, who tend to be healthier.

“This poses a problem because Pacific Islanders are at very high risk for poor health, yet receive few targeted services or research attention,” said Andrew M. Subica, PhD, an assistant professor of social medicine, population, and public health in the School of Medicine. “In general, the small population sizes of multiracial, NHOPI and AIAN populations make it hard to examine these groups individually. As a result, comparatively little is known about the health disparities of these neglected minority populations – a gap that could hide potential problems and impede the delivery of effective care.”

Using the CHIS data (2005 to 2011), Subica and his colleagues examined the prevalence of obesity, diabetes, physical disability, and poor/fair health in adults from each of the major U.S. racial minority groups (African American, Asian American, Latino, multiracial, NHOPI, and AIAN), and then compared these estimates to those of non-Hispanic whites, the dominant racial group in the U.S.

They found a rising trend in obesity and diabetes over time across all groups, with NHOPIs, AIANs, and African Americans reporting the highest obesity and diabetes rates. For multiracial, NHOPI, and AIAN adults, the odds of being obese were 1.2 to 1.9 times greater than for non-Hispanic white adults, and the odds of having diabetes were 1.6 to 2.4 times greater.

“What makes NHOPIs and AIANs important to study is that they are frequently overlooked and marginalized within the U.S. despite many of their native homelands or tribal nations suffering significant historical trauma and loss at the hands of the U.S. government,” Subica said. “For multiracial individuals, they compose the second fastest growing U.S. racial group, yet we know very little about their health. Our findings are surprising in showing that multiracial adults in California are quite health-poor, displaying a pattern of health disparities that is most similar to AIANs, who have the worst health outcomes in our study.”

To explain these disparities, Subica and his colleagues examined possible differences in social factors. They found that adults from every racial minority group studied had lower levels of education, health insurance coverage, and greater poverty than non-Hispanic white adults, but that these factors only partially contributed to health disparities. Subica speculated that exposure to racism and its negati