Obesity Rate: Increase Predicted

The weight epidemic in America is undeniable, and the numbers speak for themselves. According to the Centers for Disease Control and Prevention (CDC), 34 percent of Americans are currently obese, and another 34 percent of Americans are overweight. That leaves only 32 percent of Americans are at a healthy weight.

If you think that sounds dire, there's more bad news in store. A new study by researchers at Harvard University predicts that the obesity rate is going to climb to at least 42 percent.

The study, " Infectious Disease Modeling of Social Contagion in Networks", was published in the November 2010 publication of PLoS Computational Biology.

The study looked at the two aspects of obesity 'spread', or factors that increase the rate of obesity. One factor is the social aspect of obesity, or how obesity spreads just by having social connections with an obese person. The other factor is the non-social aspect, such as easy access to unhealthy foods.

"We find that while non-social transmission of obesity remains the most important component in its spread, social transmission of obesity has grown much faster in the last four decades," Rand, a research scientist in the Program for Evolutionary Dynamics, fellow in Harvard's Department of Psychology and Berkman Center for Internet & Society said, according to Science Daily.

The study revealed that Americans that are not obese have a two percent chance of becoming obese in any year. As far as the social spread of obesity, the study showed that for each obese social contact the person has, their chance of obesity rises another 0.4 percent.

An obese individual has only a four percent chance of losing weight to take them out of the 'obese' range, a constant statistic for almost 30 years.

Science Daily reports, ""These results suggest that social norms are changing the propensity for becoming obese by non-social mechanisms, and also magnifying the effect that obese individuals have on their non-obese contacts," the scientists write in PLoS Computational Biology."

The study also was a 'best case scenario' - meaning the obesity rate may very well go beyond the 42 percent mark the study indicated. However, the researchers point out that we may not see the peak of the obesity epidemic for another 40 years, indicating a slow incline rather than a sudden jump in cases.

The conclusion the team came up with, reported on Science Daily: "Our analysis suggests that while people have gotten better at gaining weight since 1971, they haven't gotten any better at losing weight," says lead author Alison L. Hill, a graduate student in Harvard's Program for Evolutionary Dynamics, Biophysics Program, and at the Harvard-MIT Division of Health Sciences and Technology.

Science Daily: Obesity Rate Will Reach at Least 42 Percent, Say Models of Social Contagion
PLoS Computational Biology: Infectious Disease Modeling of Social Contagion in Networks