The number of children and adults who are overweight or obese has seen a rapid increase in recent years. According to recent data from the World Health Organization, more than one billion adults globally are overweight, with more than 300 million of them considered obese. In 2005, more than 20 million children under the age of five were overweight or obese. But, Johns Hopkins University’s Youfa Wang said what these prevalence rates do not reveal is far more alarming.
“The real situation is worse than just the prevalence of obesity,” said Wang before a full room of Duke students, staff and faculty members who attended last week’s University Seminar on Global Health. “Heavy Americans have become heavier and more centrally obese.”
In his research on the gender-ethnic disparity in Body Mass Index (BMI) and waist circumference distribution, Wang, associate professor at the Center for Human Nutrition at Johns Hopkins’ Bloomberg School of Public Health, found that the average change in waist size and BMI among children (and adults) from year to year has risen sharply, with that trend likely to continue. This suggests that obesity is not only prevalent, but that people are growing more obese with time. Wang also found that obesity disproportionately affects women and African Americans.
The epidemic is projected to get worse in the next 10 to 20 years, with dire consequences. Wang projects the average health care costs for the overweight and obese will cost $507 billion in the year 2030 -– making up 17.6% of total health care costs. This is more than six times the cost it was for this group in the year 2000.
But the US is not the “fattest land,” nor does it have the fastest increase rate of obesity, according to Wang. While some researchers believe the obesity rate has largely leveled off in the US, prevalence rates are climbing much faster in places like Singapore, New Zealand, East Germany, Australia and China.
China’s rates of overweight and obese are particularly alarming for Wang, whose research between 1985 and 2005 found that obesity among Chinese school children increased five-fold. This remarkable change in disease patterns over a short time period can be attributable to a variety of social, environmental, and behavioral changes. Wang blamed sedentary lifestyles, a more westernized diet with more fatty and sugary foods, technology, international trade and cross-cultural influence.
Wang is currently adapting a successful Chicago-based obesity intervention among school-children to the urban centers of China. His intervention focuses on health education and increased physical activity during school hours. Although few school-based interventions have proven to be effective and sustainable, Wang’s intervention among African American children in several low-income neighborhoods was an exception.
“Our intervention involved the schools and parents, which had a positive impact on our results. The percentage of children who were overweight dropped from over 30% to under 20% in one year. We still saw positive results of our intervention up to five years later,” said Wang. “There is a great need for more research and health promotion programs with a focus on healthy weight and lifestyles among young people worldwide. We need to do more to reach children and adolescents early to form lifelong healthy habits.”
Wang also serves on the International Obesity Task Force (IOTF), a WHO Expert Committee to develop a new international growth standard, and on the International Union of Nutritional Sciences Task-Force on Diet, Nutrition and Long-term Health.