Researching Obesity’s Complexity and Impact

As thousands of brainiac kids from around the globe began descending on the University of Tennessee for a week of Destination ImagiNation’s creative problem-solving summer camp, researchers in health and nutrition on the Knoxville campus couldn’t help noticing that scarcely any overly plump children were in that bunch of campers.

On average, they were less sedentary than their peers elsewhere. “And leaner than the kinds of kids you see going to Wal-Mart, especially in Tennessee, where the obesity rate is extremely high,” says Dr. Naima Moustaid-Moussa, co-director of UT’s multidisciplinary Obesity Research Center, one of several campuses with obesity projects associated with and partially financed by the National Institutes of Health.

As UT launches an afterschool program modeled after Destination ImagiNation in 17 Tennessee counties, UT researchers are banking on the notion that kids who are engaged in thought, ideas and creativity also will become more mindful of nutrition as a fundamental aspect of their daily well-being. The youths will be assigned tasks similar to those undertaken during Destination ImagiNation, which, for example, had youths constructing houses—using only newspapers and tape—large enough to fit a person inside.

 “We want them to look at resources they have to solve complex problems,” says Dr. Betty Greer, a human ecology professor who helps oversee the summer camp and the pilot anti-obesity project targeting Tennessee’s youth. “We’re hoping this will make young people more tuned in to eating healthy. When people are more active, their metabolism works better and that hormone that controls hunger is better regulated.”

With Americans fatter and more malnourished than ever—almost two-thirds of the population is considered overweight or obese compared with 56 percent in the late 1980s and early ’90s, and people of color and the poor are the most obese of all—federal and university researchers and outreach workers from various anti-obesity organizations aim to make the public more mindful about its food consumption and economic toll of being too big. Some 300,000 deaths per year can be attributed to obesity, and medical costs associated with obesity are estimated at $147 billion annually. 

First Lady Michelle Obama has been shining a spotlight on childhood obesity and the risks of obese children becoming obese adults, and the health care reform law contains several provisions to fight obesity. For its part, UT is halfway through a four-year study of childhood obesity and last month began working with youth in 17 Tennessee counties. Tennessee leapt from fourth place in 2009 to second place this year in a Trust for America’s Health-Robert Wood Johnson Foundation ranking of states with the fattest people.

Researchers are also busy investigating the numerous nuances associated with obesity—a chronic disease shaded by class, race, food cultures, nutritional mindsets and household income.

“People with higher incomes can afford health clubs, bicycles, personal trainers, fresh fruits and vegetables and salmon, whereas people who are low-income may live in a food desert where there are few options for healthy food, little exercise equipment, few gyms,” says Dr. David Bassett, the UT obesity center’s other co-director. “They may not even feel safe walking the streets of the neighborhood. These are some of the discussions we have around here, the ideas that we bounce around. Some of them are proven and some are not. We’d like to believe there are simple answers, but we have to tease apart these questions of race, education and income.”

In Those Genes

There are other important variables, including differences in physiology and genetics. Heeding that reality, the body-mass index (BMI)—a nonclinical calculation of body fat—for normally weighted adults of Asian descent was set by the Centers for Disease Control at 22.9, which compares with 24.9 for most others. Muscular density, which can vary among and within ethnic groups, is also taken into account, a significant change from yesteryear when appropriate body weight was assessed by a one-size-fits-all standard.

 “Five to 7 percent of obesity cases are strictly due to genetic causes,” says Moustaid-Moussa, whose research on healthy omega-3 fatty foods will be published later this year in the Journal of Nutrition. “Obesity is a very complex question. That you can be predisposed to being overweight is one aspect of this. On top of that, there is your environment, the matter of food availability, the predisposition of many Hispanics and African-Americans to high blood pressure, high cholesterol … .”

Blacks and Latinos have had persistently higher rates of obesity than any ethnic group. Black women are at the top in that hierarchy, with roughly 50 percent of them identified as overweight (a BMI higher than 25, generally speaking) or obese (BMI of 30 or higher). That compares with roughly a third of White women, according to the latest available data from the Centers for Disease Control, National Center for Health Statistics and National Health and Nutrition Examination Survey. Other snapshots of their data show that all poor women (those living at or below 130 percent of the official poverty rate) are twice as likely to be obese than women with higher incomes. Starting out, low-income Black and White girls generally have similar BMIs but that gap widens by the time they turn 19, with Black females becoming weightier.

Income is not a statistically significant factor among men, with obesity rates remaining fairly equal across racial and ethnic groups. However, Mexican-American men are more overweight and obese than non-Latino Whites or Blacks, and non-Latino White males are slightly more overweight or obese than Black men, partly because employed Black men are more likely to be laborers, burning off the calories. Household economics also is less of a factor in whether young children are overweight, except among non-Latino White youths from poor families who tend to be fatter than youths from higher-income clans of other races.

Driving Factor

Rising diagnoses of obesity-linked Type 2 diabetes, one among several fat-related diseases, in young people is helping to drive the focus on obesity. Type 2 diabetes used to primarily afflict adults. “We’re aiming to enhance the self-management of people with diabetes, promoting healthier eating and what that means,” says nutritionist Robin Nwankwo, a diabetes educator at the University of Michigan’s Diabetes Research and Training Center in Detroit. “And we’re constantly challenged to provide that information to people with so many other factors at play: longstanding eating habits, the belief that they’ve no time to prepare food from scratch, limited access to food in the areas of Detroit and Toledo (Ohio) that we serve. Those barriers and personal preferences conflict strongly with what we’re trying to achieve.”

Spreading the word on what it takes to keep weight in check, and understand caloric intake and food ingredients that help or hinder the body is the goal of projects like the one UT is piloting for Tennessee’s youth. It also is the aim of outreach programs such as UT Extension’s online tutorials on grocery shopping, nutrition, cooking and the like, and of courses offered to UT students.

Dr. Guoxun Chen’s undergraduate course on understanding obesity averages about a dozen enrollees at a time; 28,000 students are on the Knoxville campus, the UT system’s flagship. “I try to get them to understand the genetic and environmental aspects of this,” says Chen. “I also  talk about traditions of food and metabolic processes,” including the rapid-fire absorption of processed foods and how, say, whole grain bread is better than highly processed, high-fructose white bread because the body works harder to digest and absorb whole grains.

Those are not surprising facts, given the history of food production and consumption. For example, Chen says, Arizona’s Pima Indians were lean until around 1890 when natural environmental shifts caused their crop irrigation systems to dry up.

“The United States government began subsidizing food, providing food for them. They became a population with high rates of diabetes and obesity,” Chen says, adding, however, that a contingent of Pima moved into the mountains of Mexico and kept farming. “Even today, their current rates of obesity are far lower than their American cousins. Our genes have evolved to let us be obese wherever food is abundant and there is a lack of physical activity. It takes a little bit of work to eat well.”

Government spending priorities haven’t helped promote physical activity needed to combat obesity. For example, just 2 percent of federal spending on transportation goes toward biking and walking trails, says Bassett. His survey of Ontario, Canada’s agrarian Amish, who maintain a proverbial meat-and-potato diet, consuming large portions and often chasing that with dessert, also found that community to be almost obesity-free. Its men take 18,000 steps per day and women 15,000, Bassett says. That’s three times the amount walked by the average U.S. resident.

Says Bassett: “I’ve been in this field for 22 years and I vacillate between hopefulness and discouragement. I grew up in a sort of different world, walking to elementary, middle school and high school. My parents had a vegetable garden. We never watched more than 30 minutes of television a day.”

Not so now. Half of all Black kids spend more than three hours a day in front of the tube. Blacks watch more television than any other group. And research has linked passive television watching—as opposed to play or other activity—directly to obesity.

Says Nwankwo of her hopes for the future: “We are starting to see and hear more younger adults, people in their 20s, early 30s, starting to make the connection between illness and obesity and recognizing that this is a problem. They’re being pulled into care-giving and they simply do not want that.”