Despite being thinner, Asian Americans are more likely than whites to have type diabetes 2, and the problem is growing, a new study finds.

Using data from an ongoing government health survey, researchers found that Asian Americans had consistently higher rates of type 2 diabetes than white Americans from 1997 to 2008.

What's more, diabetes rates rose over time for both racial groups, reaching 8 percent among Asian adults and 6 percent among whites.

That was despite the fact that Asian Americans were less likely to be overweight, one of the prime risk factors for type 2 diabetes.

The findings, reported in the journal Diabetes Care, are in line with past studies showing that Asian background itself is a risk factor for diabetes.

But while researchers know that Asians are at increased diabetes risk, most people are probably unaware of that, said Hsin-Chieh "Jessica" Yeh, an assistant professor at Johns Hopkins University in Baltimore and the senior researcher on the new study.

Genes are partly to blame, Yeh told Reuters Health in an email. But it's the combination of genetic vulnerability and lifestyle that's key, she pointed out.

"Asians may be even more susceptible to unhealthy food and related weight gain," Yeh said.

Specifically, studies have shown that even though Asian adults tend to weigh less than white and black adults, they often have a higher percentage of fat surrounding their abdominal organs. This so-called "visceral" fat is particularly linked to the risk of type 2 diabetes.

Then there is exercise, which is thought to help lower diabetes risk regardless of body weight. Based on health surveys, Asian immigrants to the U.S. are less physically active than native-born non-Asians, Yeh and her colleagues note.

So for Asian Americans, as for all Americans, healthy diet choices, calorie consciousness and regular exercise are key to curbing diabetes risk, Yeh said.

The findings are based on 230,500 U.S. adults who took part in a nationally representative government health survey between 1997 and 2008. Just over 11,000 were Asian American, with the majority being foreign-born.

Over the 12 years of the study, the number of Asian Americans reporting a diabetes diagnosis rose from just over 4 percent to 8 percent. Among white adults, the prevalence rose from just under 4 percent to 6 percent.

That was despite the fact that compared with their white counterparts, Asian Americans had a consistently lower body mass index, or BMI, a measure of weight in relation to height, and lower rates of obesity. In 2006-2008, 25 percent of whites were obese, versus 17 percent of Asians.

When Yeh's team accounted for factors like age, BMI, income and reported exercise levels, Asian background itself was linked to a 30 percent to 50 percent higher likelihood of having diabetes.

"The main implication of our study is that type 2 diabetes is a growing public health problem for Asian Americans that requires urgent attention," Yeh's team writes.

It's possible that their statistics aren't precisely correct, the researchers acknowledge. For one thing, they had to assume that participants answered the survey questions correctly. They couldn't account for how people of mixed race identified themselves. And they didn't have information on any other diabetes risk factors, such as what participants usually ate, and whether anyone else in their family had diabetes.

Despite these shortcomings of the study, Yeh recommends that along with making healthy lifestyle choices, middle-aged and older Asian Americans should be sure to have routine check-ups with their doctor. Blood sugar tests can detect the abnormally high levels that signal "pre-diabetes."

In some Asian cultures, Yeh noted, routine doctor visits are not the norm, and that could be one factor in Asian Americans' higher diabetes rate.