HEALTH AT ANY SIZE

Nutrition researchers Judy Stern, left, and Linda Bacon found that self-acceptance and attention to hunger cues were more important than diet plan in improving obese women’s health. (Photo: Debbie Aldridge/UC Davis)

Behavior change and self-acceptance trump dieting hands-down when it comes to achieving long-term health improvements in obese women, according to a two-year study by UC Davis nutrition researchers.

The findings suggest that significant improvements in overall health can be made, regardless of weight loss, when women learn to recognize and follow internal hunger cues and begin feeling better about their size and shape.

“We have been ingrained to think that large people can make improvements in their health only if they diet and slim down,” said nutrition professor Linda Bacon, who conducted the study with Judith Stern, professor of nutrition and internal medicine. “But this study tells us that you can make significant improvements in both metabolic and psychological health without ever stepping on the scales or counting calories. You can relax about food and eat what you want.”

Although this study included only women, the researchers say that there is no reason to believe that the results would be different for men.

For years it has been known that obesity is associated with a number of serious health problems, including heart disease, diabetes, stroke and even some cancers. To avoid such medical complications, health professionals have encouraged their obese patients to lose weight. But dieting has not proven successful in the long run. Lost weight is usually regained, with no improvements in health indicators such as blood pressure or cholesterol levels.

Faced with dieting’s dismal track record, the rising prevalence of obesity and the premise that obesity itself may be relatively benign compared with health habits, nutritionists and health professionals began to look for a more effective way of dealing with the health risks. One approach called “Health at Every Size” encourages obese individuals to pay more attention to internal body cues that signal hunger and fullness instead of counting calories.

In the UC Davis study, researchers compared the weight, health and attitudes of 39 women ages 30 to 45 who dieted with that of 39 women who followed the Health at Every Size program.

Members of the dieting group were told to moderately restrict their food consumption, maintain food diaries and monitor their weight. They were provided with information on the benefits of exercise, behavioral strategies for successful dieting, measuring calories and fat content, reading food labels and shopping for appropriate foods.

Participants in the nondieting group were instead counseled to pay close attention to internal body cues indicating hunger or fullness, and to how the food made them feel. They also received standard nutritional information to help them choose healthful foods and participated in a support group designed to help them understand cultural influences and become more accepting of their larger bodies. In addition, they were encouraged to identify and deal with barriers, including negative self-image, that might get in the way of enjoying physical activity.

Ninety-two percent of the nondieting group stayed in the study throughout the treatment period, while 42 percent of the dieters dropped out before the study’s end.

In other results:
• The nondieters maintained their same weight. The dieting group lost 5.2 percent of their initial weight in the first 24 weeks but regained almost all of it by the end of the two-year study.

• The nondieters showed an initial increase in their total cholesterol levels, but this significantly decreased by the end of the study, as did their levels of LDL cholesterol or “bad” cholesterol. The dieters showed no significant change in cholesterol levels at any time.

• Both groups significantly lowered their systolic blood pressure during the first 52 weeks of the study, but only the nondieters sustained the improvement.

• After two years, the nondieters had almost quadrupled their moderate physical activity. The dieting group, after significantly increasing their physical activity, slipped back to their initial levels by the end of the study.

• Self-esteem and depression improved significantly for the nondieters, while self-esteem dropped among the diet group.

The research was funded in part by the National Institutes of Health, the U.S. Department of Agriculture’s Western Human Nutrition Research Center and the National Science Foundation. Findings appeared in the June issue of the Journal of the American Dietetic Association.

— Pat Bailey

CENTENNIAL: SPLITTING OF THE BARK

Horse-drawn buggies plied unpaved roads in Davisville in the early 1900s when the town vied for the University Farm.

NAMESAKES: HART HALL

George Hart 1883-1959

Veterinarian George Hart helped put the science in animal science. Later, he helped launch the School of Veterinary Medicine.

Livestock breeders responded with skepticism in 1926 when Hart—previously a veterinary science faculty member at UC Berkeley and veterinarian for the city of Los Angeles and the federal government—was appointed chair of what was then the Division of Animal Husbandry at Davis.

The division up until then had focused on teaching two-year nondegree students how to raise champion livestock. Hart soon hired to the faculty nutritional biochemists, a geneticist and a physiologist— with the then-revolutionary idea that advances in livestock production would come through fundamental biological sciences.

Claude Hutchison, former dean of agriculture for the entire UC system, said later that one rancher told him at the time: “The trouble with George is he’s too sciencey.”

The livestock industry would come to appreciate Hart’s scientific approach. In 1940, Hart was selected president of the American Society of Animal Production, now the American Society of Animal Science. In 1947, the society honored Hart for his research in animal nutrition and reproduction by hanging his portrait at the International Livestock Exposition in the Union Stockyards in Chicago. The portrait now hangs at the Saddle and Sirloin Club in Louisville, Ky.

Hart’s new approach was officially recognized when the Division of Animal Husbandry was renamed the Department of Animal Science.

He went on to touch the entire campus. He helped establish some of its first graduate groups, drawing on faculty from Davis, Berkeley and San Francisco to teach graduate students in physiology, genetics and nutrition.

Hart also worked with other faculty members and administrators to plan the curriculum and buildings for the new School of Veterinary Medicine. Shortly before the first class of students enrolled in fall 1948, Hart was named dean, a post he held until his retirement in 1954.

— Kathleen Holder

ENEMIES WITHIN

Trapped in your DNA, and that of all mammals, is the molecular wreckage of ancient viral invaders that once plagued our ancestors. It has long been assumed that these “endogenous retroviruses” (ERVs) in our genome were either meaningless genetic debris from humanity’s ancient pandemics or that viral genes had been domesticated and rendered benign, or even beneficial, by evolution.

But UC Davis Medical Center Assistant Adjunct Professor of Surgery Kiho Cho doesn’t believe ERVs are always harmless. They can be dangerous, he believes—and may just be the key to a new generation of treatments for patients with afflictions as diverse as burn traumas, autoimmune disease and cancer.

A little understood tragedy of burn trauma is that many patients survive an automobile crash or house fire, only to die days or weeks later from multiple organ failure. Their livers, kidneys and lungs simply quit.

“Some burn patients survive while others—people the same age, race, sex and with similar trauma—are unable to survive,” Cho said. “But why do organs fail when the injury is to the outside of the body?”

Many scientists believe that complex chemical signals are involved—molecular cascades triggered by burns that somehow overwhelm internal organs. Four years ago, Cho joined the search for those signals, in mice. His team discovered several genes that were activated in the liver after skin burns. But one gene stood out as particularly intriguing.

“We found an endogenous retrovirus sequence, structurally very similar to the ‘mouse AIDS’ virus—an immunosuppressing virus,” Cho explained. Burns on the skin somehow activated this ancient viral gene in the liver.

If similar ERVs reacted that way in other organs, Cho realized, they could overwhelm burn patients’ immune system in major organs. And that could explain why some patients survive burns that kill others. Patients who survive, he hypothesizes, may have different ERV profiles in their genome than those who are killed by similar trauma. More importantly, if ERVs play a central role in burn mortality, there may be an unexpected way to save many patients.

“If burns activate ERVs that suppress the immune system and contribute to organ failure,” he explained, “we may be able to use anti-retroviral drugs developed for AIDS, to save many burn patients.”

Since that initial discovery of a burn-activated ERV in the mouse liver, Cho’s team has discovered ERVs in other organs—and as predicted, they behave similarly after burn trauma.

The medical implications may extend well beyond the treatment of burn victims. Recent studies in Canada, England and the University of Kentucky show that activated ERVs produce toxic proteins in the brains of multiple sclerosis patients, killing neurons and hastening the deadly progression of the disease.

Activated ERVs have also been identified in the brains of schizophrenics. If Cho’s research leads to a new paradigm in the understanding and treatment of burn victims, he hopes, it may also one day soon shed new light on how we can confront cancer, autoimmune disease and perhaps even mental illness.

— Bryant Furlow

CLEANING THE AIR AT SCHOOL

With the help of UC Davis pollution expert Thomas Cahill, teams of students at three local high schools are helping improve the air they breathe.

Cahill had previously found dangerously high levels of pollutants around public schools in the Sacramento area in a study he had conducted for the American Lung Association’s Health Effects Task Force. They decided to combat the problem by working with students through the association’s existing high school program that dealt with issues such as tobacco-use prevention. The joint program now operates at Davis Senior High, and Mira Loma and Luther Burbank in Sacramento.

Students in the program were given full responsibility for designing their projects. They each created an inventory of possible pollutants, from the school’s heating and cooling systems, to nearby roadways and dust in the classroom. Then, over a two-week period in February, all three schools measured the particles in the air on their campuses, using equipment originally designed and built at UC Davis for the National Science Foundation’s massive 2001 study of Pacific Rim pollution. The students were able to perform continuous measurement of particles day and night by mass, size and composition, thus tracking daily events and weather. They are now combining these data with their other findings into a comprehensive report.

Every school had a different pollution profile, and the specific chemistry of each school’s air pollution is still being studied. For now, the reports put together by the students will create a template by which other schools can design their own study.

“It forced the students to do calculations, do algebra, set up spread sheets,” Cahill said. “It really took the science that they had learned in the classroom and made it very personal. We kept putting it back on the students that ‘the answer is not in the back of the book.’”

The last step has been to design solutions for the pollution problems. Students at Mira Loma were able to improve their school’s air quality simply by growing grass over a small barren patch to reduce the dirt tracked into the classroom. At Luther Burbank, students have gotten approval from the principal to plant a barrier of trees to protect the school from pollution from nearby Florin Road.

“We’ve got a lot of support from the school districts,” Cahill said. “We envision a continuing effort with the Lung Association of Sacramento designing an air analysis model that will be used by schools all around the state.”

— David Owen