Is the rate at which one ages biologically affected by ethnicity and environmental factors?

A recent study from the University of Hawaii at Manoa has found evidence that it is and that Native Hawaiians experience higher rates of accelerated biological aging compared with white and Japanese American residents in the state.

“On average, there are nearly 25% more Native Hawaiians than white participants that exhibited faster than normal biological aging,” said Alika Maunakea, lead author of the study. “This appeared to be associated with health such as obesity and living in a poor neighborhood.”

The study also found that independent of ethnic background, living in adverse environments, such as a neighborhood with low socioeconomic status, appears to be associated with accelerated biological aging.

But results also showed life experiences can mitigate this, according to Maunakea, a Native Hawaiian professor of epigenetics and health disparities researcher at the University of Hawaii at Manoa John A. Burns School of Medicine.

“We observed that despite living in socioeconomically poorer neighborhoods, individuals who engaged in higher physical activity, had a higher level of education attainment, and healthier diets tended to have closer to normal biological aging, which was independently associated with lower BMI and lower risk for diabetes,” he said.

Biological aging refers to the gradual deterioration of cellular and physiological functions over time, according to Maunakea. It reflects the body’s true age at a molecular and cellular level, which can differ from a person’s actual chronological age.

For the study, published in July in the Journal of the American Medical Association, Maunakea and his team analyzed DNA samples from 376 adults from the UH Cancer Center’s ongoing multiethnic cohort to determine their biological age.

Among them were healthy Hawaii residents who self-­identified as Japanese American, Native Hawaiian or white.

Using an epigenetic process called DNA methylation, they estimated the biological age of each participant as well as whether there were differences based on variables including education, diet and exercise.

According to Maunakea, the measure of how quickly or slowly someone is aging biologically is based on a ratio derived from DNA methylation data. The higher the ratio, the higher the rate of biological aging.

The difference between Native Hawaiians and whites was about 10%, he said, which, based on an 80-year life span, means an eight-year difference in longevity. Those with higher rates of obesity also had higher ratios, or higher rates of biological aging, than those of normal weight.

Maunakea hopes the study sheds light on biological mechanisms that help to explain the origins of health disparities in Native Hawaiians, who have a higher risk for conditions such as diabetes, obesity, heart disease and certain cancers when compared with all other major ethnic groups in Hawaii, in order to better address them.

The study results are personal for Maunakea, who was born and raised in Waianae, where he has witnessed family members struggle with diabetes and cancer.

“To me, the results are further proof that lifestyle matters to health and that as individuals we can do something about it,” Maunakea said. “Being Native Hawaiian doesn’t make us destined for disease, even if you live in poor neighborhoods. Our data at the molecular level shows clearly that engaging in healthier lifestyles reduces the risk for disease and likely improves longevity. This gives me hope that we can, in my lifetime, improve the overall health and well-being of our lahui.”

He also hopes results of the study can help shape health policy and investment in programs that increase education and healthy lifestyle choices among Hawaiians.

One such program is MAO Organic Farms in Waianae. In an earlier study, he said, results showed the farms’ culture-based youth program, which incorporates leadership skills along with better diet and healthier lifestyle habits and education, reduced the overall risk for diabetes.

In a separate study, Maunakea is also examining whether socio-ecological determinants factor into diabetes risks in Native Hawaiians and Pacific Islanders in Hawaii.