A new comparison of multi-national data, released this month, reveals that highly educated women have a healthier average weight than less educated women, but that the meaning of healthier changes according to a nations relative wealth. In countries where malnutrition is prevalent, better-educated women weigh more. But in wealthier countries with rapidly growing rates of obesity better-educated women weigh less.
As a population moves through the nutrition transition, it is the most educated, and highest income, who are the first to exit under-nutrition. They are also the first to adjust their diet and physical activity to avoid the deleterious effects of being overweight, explained John Strauss, professor of economics at the University of Southern California.
It appears that it is women who tend to lead this transition, he added.
More than half of the adult population is underweight in Bangladesh, the poorest country analyzed by Strauss and Duncan Thomas (Duke University). In Bangladesh, average female body mass increased with every additional year of schooling.
In contrast, only 1 percent of people in the United States are underweight. Better-educated women in the United States, the wealthiest country in the study, had a lower average body mass index the more education theyd received, the researchers found.
Obesity rates rise with economic development which is troubling given the relationship between obesity and cardiovascular disease, stroke, diabetes and possibly cancer, Strauss said. For example, the researchers show that almost twice as many women are now overweight as are underweight in China.
Furthermore, in developing countries worldwide, women are more likely than men to be overweight or obese. The gender gap is largest in South Africa, where more than one-third of women are obese, compared with about 10 percent of South African men.
However, Strauss and Thomas show that once women receive a certain amount of schooling, average body mass index (BMI) falls and they are more likely to be at a healthy weight.
Behavioral changes have important impacts on health outcomes, Strauss said.
For example, the average BMI of a Mexican woman where 74 percent of the women are overweight or obese declines for every year of schooling she receives in excess of just five years. There is a similar sharp decline in the average females BMI in South Africa after five years of education.
BMI is a widely used measure that accounts for both weight and height.
The United States was the only nation surveyed in which better-educated men had a lower average BMI than less-educated men. In every other country, the average male body mass increased with every additional year of schooling.
|Contact: Suzanne Wu|
University of Southern California