"We want to alert the science community that people are not immune to this epidemic just because they live in non-industrial or poor populations," Marquisa La Velle of the University of Rhode Island said today.
La Velle was one of several researchers who discussed the biological and cultural factors behind the worldwide trend toward excessive fatness, during the American Association for the Advancement of Science (AAAS) Annual Meeting in Boston today.
In December 2001, the United States Surgeon General released a report warning that obesity could soon kill more Americans than tobacco smoke. In industrialized nations, obesity is associated with an increased risk for diabetes, cancer, cardiovascular, and digestive diseases.
Until recently, these disorders have paled in comparison to the health challenges posed by famine and infectious disease to lower and middle income countries in Asia, Africa, the Middle East, and Latin America.
But now, the developing world faces rapid shifts in urbanization, technology, food processing, and even leisure time, and all these factors contribute to the rise of obesity in these countries, said Barry Popkin of the University of North Carolina at Chapel Hill. Popkin suggested that countries still addressing the problems of under-nutrition need to give "far greater emphasis" to the prevention of obesity-related diseases.
Data collected from around the world illustrates how different environmental and cultural conditions contribute to obesity in urban and rural populations. Paradoxically, childhood malnutrition and stunted growth may be found hand-in-hand with adult obesity in many places, said William Leonard of Northwestern University, who studies nutrition in Siberian populations. La Velle, and researcher Stanley Ulijaszek of the University of Oxford, are investigating similar phenomena in populations in South Africa and Australia, and New Guinea, respectively.
"The cultural conditions for obesity are often already there in these populations, but something is stopping them from causing obesity in younger individuals," said La Velle, who noted that a significant disease load might play some part in this "masking effect" in Australia.
Obesity is also on the upswing among non-western immigrants to industrialized countries, as well as certain western groups undergoing rapid socioeconomic changes.
Barry Bogin of the University of Michigan Dearborn presented the case of the Maya in Guatemala and Maya in the United States, and discussed the impact of immigration on Mayan children.
While Maya-American children are taller and have longer legs than their Guatemalan counterparts, "an alarming number of Maya-American children exhibit weight problems," said Bogin, who noted that 42 percent of Maya-American children would be classified as obese by the standards set by the Centers for Disease Control.
Bogin's recent survey of these children suggests that variables like time spent watching television and playing computer games, along with family size and the primary language spoken at home, are some of the factors that influence the children's risk of obesity.
The American Association for the Advancement of Science (AAAS) is the world's largest general scientific society, and publisher of the journal, Science. Founded in 1848, AAAS serves 134,000 members as well as 273 affiliates, representing 10 million scientists.