Much too slim for most of America. (Duane Burleson/AP Photo)

Crash test dummies have long helped auto manufacturers keep cars as safe as possible, but the slim plastic mannequins are increasingly poor mirrors of the modern American man and woman.

So the world's leading producer is making a fatter version.

Humanetics, which manufactures most of the crash dummies used to clear cars for sale in the United States, is in the process of developing a new obese dummy to better mirror the U.S. population. The company already has a version in the works that weighs more than 270 pounds and has a body mass index of 35 (30 and above is considered obese by the CDC).

Obesity has risen to an untenable level in the country. As of 2012, some 35 percent of Americans were obese, and nearly 70 percent of the population was overweight.

obesity

The costs of the country's growing weight problem has been steep from both a health and economic perspective. But its ever-expanding waistline has also made it more difficult for traditional crash test dummies to properly model how car passengers' bodies will react during an auto accident. "Obese people are 78 percent more likely to die in a crash," Chris O' Connor, the CEO of Humanetics, told CNN on Tuesday. "The reason is the way we get fat. We get fat in our middle range. And we get out of position in a typical seat."

A 2010 study from the University at Buffalo and Erie County Medical Center reached a similar conclusion. The study, which analyzed data from more than 150,000 car crashes in the United States between 2000 to 2005, found that moderately obese drivers faced a 21 percent increased risk of death, and morbidly obese drivers faced a 56 percent increased risk of death. "Crash test dummies have saved lives and provided invaluable data on how human bodies react to crashes, but they are designed to represent normal-weight individuals," lead author Dr. Dietrich Jehle told the Daily Mail in 2010.

Humanetics is also looking to develop a prototype for a crash test dummy that better models older drivers, who also face increased risks of serious injury. Critics have also pointed out the inadequacy of child test dummies, which have been designed by scaling down adult dummies rather than developed separately.