Center for Alaska Native Health Research tackles a heavy subject

Obesity has risen to epidemic levels in the United States during the past two decades. Between 1976 and 1980 about 15 percent of U.S. adults were classified as obese. By 2004 that number more than doubled to a whopping 33.9 percent.

If the trend continues, 75 percent of the U.S. population will be overweight within the next five years and 40 percent will be obese.

Obesity causes devastating and costly health problems, reduces life expectancy and is a significant risk factor for type 2 diabetes, heart disease and certain cancers. It is also associated with depression, stigma and discrimination. These escalating rates of obesity and associated health problems are placing a significant burden on the health of our nation and our health care system.

The problem is obvious. The solution seems simple: eat less and exercise more. The reality is much more complicated; ask anyone who has tried to lose weight and keep it off.

An overly ample diet and lack of physical activity are not the only culprits. There is considerable scientific evidence that a combination of genetic and environmental components lead to the development of obesity. A group of scientists at UAF are tackling obesity through an unusual scientist-citizen collaborative research program focusing on genetics, diet, physical activity, culture and behavior.

Alaska at the fore of obesity research
The Center for Alaska Native Health Research (CANHR I) was established in 2000 by a grant from the National Institute of Health to investigate weight, nutrition and health in Alaska Natives from genetic, dietary and cultural-behavioral perspectives at the Institute of Arctic Biology at UAF. CANHR II continued and expanded this work with a second five-year grant from the NIH in July 2007.

“We want UAF to be a major partner in doing biomedical health-related research with Alaska Natives,” says Gerald Mohatt, CANHR director and UAF professor of psychology. “The work we do should inform policy and practice. It will give communities insights into the prevalence of diseases and identify both the protective and the risk factors for these chronic diseases.” 

Developed in partnership with the Yukon-Kuskokwim Health Corporation, CANHR emphasizes culturally relevant approaches to understanding and preventing health disparities in Yup’ik Eskimos using a community-based participatory research model. Traditionally, members of a community being studied are not actively involved in designing research projects and might never know the outcome of the research or any of the findings.

In community based participatory research models, community members and organizations play a direct role in the design and application of scientific study in many, if not all, phases of a project. Participants in CANHR projects own their specimens and their data. “We’re true, equal partners,”
Mohatt says. The participatory process is critical if research is to be acceptable, valid and useful to Native communities, say CANHR researchers.

CANHR scientists began the CBPR process by meeting with the regional medical director, health corporation executives and Native leaders in southwest Alaska to explain their research goals and to identify overlap with the health concerns of village communities. The groups continue to meet regularly to talk about research interests, priorities, study design, data interpretation, dissemination and application of results.

It was in such discussions during CANHR I that important health issues were identified that scientists are now investigating in CANHR II, says Bert Boyer, CANHR co-director and UAF molecular biologist and geneticist.

Research projects
Three themes guide the CANHR scientists: They seek new knowledge that can ultimately be applied to prevent and reduce health disparities in indigenous communities, they study how cultural variables influence the understanding of disease and risk to ensure research and intervention can be culturally acceptable and appropriate, and participants in CANHR projects are actively involved in project design, implementation and dissemination.

Seven major research projects are currently supported by CANHR.

Diet and nutrition
The diet and nutrition project, led by UAF nutrition and foods specialist Bret Luick, investigates which nutritional factors contribute to an individual’s weight and how weight contributes to overall health. Luick’s team records the amounts and types of traditional and store-bought foods study participants eat and why individuals choose those foods. For each participant, the scientists also record height, weight and percent of body fat.

Of particular interest to Luick’s team is vitamin D, which in its biologically active form plays an important role in regulating levels of calcium and mineralization of bone in humans. His research showed some of his study participants had half the recommended daily calcium intake level. If an individual’s calcium level is too low, their body recognizes the deficit and a hormone called parathyroid (PTH) seeks to replenish calcium by taking it from bones, which leads to loss of bone mass. Luick’s group will be pursuing this further to determine if diet intervention using calcium can lower PTH levels.

Cultural understandings of health
The cultural understandings of health project, led by Cécile Lardon, UAF assistant professor of psychology, studies how culture and health are related in a Yup’ik village. For the past three years, Lardon’s team, which includes members of the host community and the regional tribal health corporation, has investigated health, wellness, stress and coping styles as a means to develop a community-based health promotion program designed to reduce cardiovascular disease by increasing physical activity, consumption of traditional foods and stress management.

The NIH recently awarded Lardon a two-year grant to further develop this project. “Physical activity, traditional foods, and managing stress are the three areas which were identified by community members as what they wanted,” Lardon said. “This project provides an opportunity to integrate scientific knowledge with indigenous knowledge and traditions to improve the cardiovascular health of Alaska Native people.”

Lardon hopes that the group of project leaders in her host community can become a traveling training team for other communities that want to do similar health promotion.

Genetics of obesity
The genetics of obesity project, led by Boyer, seeks to identify genes or genetic markers that play a role in why some people are more susceptible than others to becoming obese. Humans’ genetic predisposition to store fat is essential for life—as stored energy, heat insulation and shock absorption—and for most of early human history that predisposition enabled humans to survive months of starvation. Now it threatens the health of more than half of the U.S. adult population.

While starvation continues to be a critical issue for about one-third of the world’s population, according to the World Health Organization, in much of the world an abundance of food and reduced physical activity have contributed to humans storing so much fat that their health is compromised.

“Your level of obesity is determined by genes and the environment,” Boyer says. In other words, genes do not function in a vacuum. “Obesity is a common disease involving multiple genes, each with a small effect on obesity and each influenced by environmental signals,” says Boyer. Native Alaska communities, which are often isolated, offer scientists an environment in which the activities people can engage in, the available foods and the environmental influences are relatively limited. “It helps to simplify things,” Boyer says. “You’re looking for a needle in one haystack rather than five haystacks.

“These common genes and environment signals are shared in Western [non-Native] populations, but in those populations there are many more factors from which to pick.”

Boyer’s team collects blood samples from study participants and analyzes the DNA for genetic risk factors that may contribute to the prevalence of obesity. Boyer’s group also collects individual and family health histories. “In CANHR I we realized that Yup’ik Eskimos have a really, really low incident of type 2 diabetes and we wanted to know why,” says Boyer. “I hypothesize that a diet rich in polyunsaturated fatty acids, called PUFAs, such as omega 3 found in fish, is protective.” By comparing genes associated with obesity, diet and health history for study participants, Boyer hopes to determine if what an individual eats can change their risk of developing obesity.

“What we learn from our Yup’ik study partners should be relevant to other populations,” says Boyer, who takes his food cues from what he’s learned and now maintains a subsistence-like diet.

CANHR II
Four new investigators will expand CANHR’s themes of obesity and chronic disease risk factors to include dietary biomarkers, stress, contaminants in subsistence foods and cultural understanding of diabetes.

“We’re trying to build a set of projects in CANHR II that will allow us to improve our understanding of diet, nutrition, physical activity, stress and cultural understandings of behavior,” says Mohatt.
Dietary biomarkers Diane O’Brien, assistant professor of biology and wildlife at UAF, leads a CANHR II project with a novel approach to assessing what an individual has eaten. Naturally occurring chemical variations in foods, called isotopic signatures, are incorporated into human tissues and reflect diet at the time the tissue was formed.

O’Brien’s group hopes to use human hair as an easy, inexpensive, noninvasive way to identify isotopic signatures and thereby accurately describe dietary differences between individuals. The longer an individual’s hair, the longer their potential dietary record may be.

Every food item, whether fish or moose or corn syrup or potato chip, contains a specific collection of isotopic signatures which form that food’s dietary biomarker. These biomarkers can help scientists accurately compare what a person eats with particular body types that are related to health, specifically to risk of obesity and diabetes.

O’Brien’s “hair test” is expected to be a more accurate measurement of diet than individual food frequency questionnaires which, according to Boyer, are only about 20 percent accurate
.
Yup’ik perceptions of body weight and diabetes
Elaine Drew, a medical anthropologist and assistant professor of psychology at UAF, is leading a project investigating Yup’ik perceptions of body weight and diabetes. One of Drew’s goals is to develop culturally appropriate intervention and prevention programs tailored to the strengths and constraints of village life.

Previous research in Native communities suggested that overweight and obese individuals were perceived as healthy and strong. “As one elder remarked, ‘a fat wife is a sign of a successful hunter,’” Drew says. “This statement prompted me to think about how we really don’t know how different communities conceptualize body shape, weight, and diabetes.”
 
To more fully understand individual perceptions of body image, Drew, in collaboration with a Native artist, developed a set of body-image cards illustrating a range of nine body types from underweight to obese. Study participants are asked to identify which shape is closest to their own and what they associate with different shapes. This is only one part of Drew’s project and is still underway, but she said the results are enlightening. How an individual perceives body shapes and weights likely affects how and whether they respond to suggestions to monitor diabetes risk or modify health behaviors, Drew said.

Yup’ik experience of stress and coping
John Gonzales, assistant professor of psychology at UAF, leads the Yup’ik experience of stress and coping project in CANHR II. Gonzales’ project grew out of conversations with CANHR I participants in which community members expressed widespread concern about the negative health consequences of stress and traumatic life events. Gonzales’ goal is to develop stress management interventions based on traditional Yup’ik values and traditions that have been tentatively identified as protective against stress.

“We want to understand risk factors related to stress, but we don’t know what the stressors are, how they are understood within the communities and how individuals cope with stress,” Mohatt says. 
Gonzales’ project is a direct result of the CBPR approach of CANHR scientists. “Sometimes it was members of the community who said things like ‘I wish you would investigate stress and its role in the development of diabetes,’” Boyer said “And now we have an investigator in CANHR II who is investigating stress as a risk factor in diabetes and obesity.”

Contaminants in subsistence foods
The availability of store-bought foods, which are often less nutritious than subsistence alternatives, has led to a shift from a subsistence-based lifestyle to a more Western one in many Native communities. At the same time, global factors such as pollution from pesticides and heavy metals are contaminating traditional food sources. Todd O’Hara, UAF associate professor of wildlife toxicology, will lead a project to assess the nutrients and contaminants in the subsistence foods of their study population. The project will evaluate the changes in nutrient and contaminant composition of raw foods and foods that
have been smoked, dried or cooked.

“We had people during CANHR I say, ‘We want to know if our subsistence foods are healthier for us to eat, even if they have contaminants, than buying things in our stores,’ ”Boyer says. “The elders want to know any information that will benefit the health of their children.”

O’Hara’s goal is to develop a model for assessing contaminant risks and nutrient benefits of several key subsistence foods which can be used by public health officials to develop effective food-related interventions.

A positive impact
“The overall goal of CANHR is to achieve a permanent and sustainable research center at the University of Alaska Fairbanks to investigate obesity and chronic disease-related risk, control and prevention among Alaska Natives,” Mohatt says. “We want our research to have a positive impact on the health of Alaska Natives.”

Mohatt envisions CANHR expanding to address other health disparities including alcohol abuse, suicide risk, cancer and smoking. Mohatt would also like to see all CANHR scientists follow Boyer’s lead in obtaining independent investigator funding, called RO1 grants, from NIH. Boyer received a $2.8 million RO1 grant to expand his study of how PUFAs and physical activity may modify genetic risk factors associated with obesity.

“The biggest success of CANHR is that we’ve provided health information to people and communities from this research,” says Mohatt. “The second success is Bert’s RO1 and the potential for him to be able to continue long-term research that will help individuals and communities understand and control what’s happening to them.”

Funding:
The Center for Alaska Native Health Research is funded by a Center for Biomedical Research Excellence grant from the National Center for Research Resources, part of the National Institutes of Heath.

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