Car safety is a big issue, therefore crash-test dummies are now packing on pounds to help protect overweight Americans in car crashes. According to Chris O' Connor, CEO of Humanetics, the only U.S. producer of the dummies, studies demonstrate that obese drivers are 78 percent more likely to die in a car crash.

He further added that crash-test dummies are usually modeled after a person who weighs about 167 pounds with a healthy body mass index.

Humanetics is developing new dummies based on the measurements of a 270-pound person with a BMI of 35, which the Centers for Disease Control and Prevention (CDC), and other health groups, consider morbidly obese.

Air bags, seat belts and other safety features are designed for thinner people and don't fit heavier people the same way, O' Connor said.

The studies have pointed that such drivers are at greater risk in car crashes. In 2010, researchers from Erie County Medical Center and University at Buffalo examined more than 150,000 crashes in the US and found that drivers moderately obese had a 21 percent increased risk of death. The study also found that morbidly obese drivers were 56 percent more likely to die in a crash.

Dr. Mark Reiter, who is the president of American Academy of Emergency Medicine, said he was unaware of differences in injury patterns between fat and thin drivers, but he added that obese victims of car crashes can be difficult to treat.