Lack of Exercise Blamed for Expanding Waistlines

According to the latest research, Americans’ lack of exercise is a much greater contributor to the nation’s alarming obesity rate than overeating or a poor diet.

The data for the study, which was analyzed at Stanford University, was published this month in the American Journal of Medicine. The data was collected for the National Health and Nutrition Examination Survey (NHANES) and considered information collected over two decades.

Most concerning are the findings that increased waist circumference — now a known risk factor for both cardiovascular disease and all metabolic disorders including Type II Diabetes — is rising even among those without significant weight problems.

Caloric intake aside, living what is commonly referred to as a sedentary lifestyle — one where almost all of one’s leisure time is spent relaxing, whether on the couch in front of the television set or at a desk behind a computer — is enough to raise your body mass index (BMI) to unhealthy levels.

When analyzed by Stanford University research scientists, the data indicated that the number of American women who reported zero physical activity climbed from 19.1 percent in 1994 to 51.7 percent in 2010. The results for men were similar: 11.4 percent in 1994 to 43.5 percent in 2010.

In general over the same 20-year period, the average BMI has increased dramatically with the greatest rise seen in young women between the ages of 18 to 39.

“We found a significant association between the level of leisure-time physical activity, but not caloric intake, and the increases in both BMI and waist circumference,” explained lead study author Uri Ladabaum, MD, MS, Associate Professor of Medicine (Gastroenterology and Hepatology), Stanford University of Medicine. Basically, American diets in general seem roughly the same over both decades, while exercise has declined dramatically.

For instance, researchers found similarities in the total daily calorie, fat, carbohydrate, and protein consumption over two decades, yet the obesity rates have risen steadily over the same period. And while this is not meant as a directive to make claims that the American diet could not use an overhaul, it does raise the meaningful nature of the importance of daily exercise.

Most importantly, the researchers note, is the rise in abdominal obesity or waist circumference, which is considered a mortality factor even among those of normal weight and BMI. Physicians currently define abdominal obesity by a waist circumference of 34.65 inches (88 cm) or greater in women and 40.16 inches (102 cm) for men.

Worse For Women

“The prevalence of abdominal obesity has increased among normal-weight women and overweight women and men,” says Dr. Ladabaum. “It remains controversial whether [being] overweight alone increases mortality risk, but the trends in abdominal obesity among the overweight are concerning in light of the risks associated with increased waist circumference independent of BMI.”

The findings are significant, especially when broken down across specific demographics.

When respondents were grouped by age/ethnicity and age, researchers found that “more than 50 percent of the workforce-aged adults in eight demographic subgroups reported no leisure time physical activity.” African American and Mexican American women, for example, showed the greatest decreases in physical activity.

That information may in turn help health professionals target specific groups who may need information as well as assistance.

“Our findings do not support the popular notion that the increase in obesity in the United States can be attributed primarily to sustained increase over time in the average daily caloric intake of Americans,” says Dr. Ladabaum. “Although the overall trends in obesity in the United States are well appreciated and obesity prevalence may be stabilizing, our analyses highlight troublesome trends in younger adults, in women, and in abdominal obesity prevalence, as well as persistent racial /ethnic disparities.”

Mindful Eating

In an unrelated study conducted this month at the University of Missouri, researchers found that traditional dieting is not as effective as “non-diet” approaches to weight management, especially for women.

The reasoning behind the findings is largely based on the common cycle of dieting and losing and then gaining the lost weight as well as added pounds after the diet is stopped, a problem that plagues many dieters, especially women.

Known as weight cycling, the behavior is considered more harmful than never losing weight according to Lynn Rossy, a health psychologist for the university. Much more effective, says Rossy, is to adopt more mindful eating behaviors that focus not on losing weight specifically, but eating for better overall health because it creates more positive relationships with food and your body.

“Intuitive eating and mindfulness are two relatively new intervention approaches that have been effective in supporting healthy eating and body image,” says Rossy. “[Mindful eating] encourages individuals to become more engaged with their internal body signals and not the numbers on the scales.”