It's not often that a scientific study suggests there are advantages to being overweight.
But a recent study by the University of Michigan Transportation Research Institute suggests that chubby men actually stand better chances of surviving automobile crashes -- provided they wear seat belts.
How fat must you be?The study, by Michael Sivak and Jonathan Rupp, indicated that belted drivers with a body mass index, or BMI, of 35 to 50 have a 22% lower probability of being killed in a crash than belted drivers with a BMI between 15 and 18.4.
BMI is a calculation based on weight and height, and the CDC uses it because, for most people, it correlates with their amount of body fat. Anyone with a BMI of 30 or more is considered obese. At 30 BMI, we're talking about someone who is 5 feet 9 and weighs at least 203 pounds. If your BMI is 45, you're hauling around more than 300 pounds at that height.
Ladies: This does not apply to you. Although rotund fellows fare better than thinner men in serious accidents in which they are wearing seat belts, the same is not true for heavy women. Belted females with a BMI between 35 and 50 have a 10% higher probability of being killed in a crash than women with a BMI between 18.5 and 24.9, the study indicated. Underweight women had an 8% higher probability of death than women of normal weight.
Obese folk are at a disadvantage if they forgo the seat belts, according to the study. Unbelted fat men had a 10% higher probability of dying than skinny guys who weren't belted. There was no statistically significant difference among BMI categories for unbelted women, although for belted women, those with a normal BMI had the lowest risk of being killed.
What to think?The researchers believe that at some point there is an "optimal balance" between the extra cushioning from body fat and the additional "mass and momentum" that is generated by a large person. A skinny guy simply can't take a punch as well as a bigger guy. But the big man is going to hit an immovable object -- like a steering wheel or a guardrail -- with much greater force than the small man, so the seat belt is key. Unbelted, that massive guy is much more likely to overload the car's air bag than the lean fellow.
The study is based on data from 300,000 drivers in fatal crashes recorded by the National Highway Traffic Safety Administration from 1998 to 2008. More than 50% of the people involved in these crashes were killed, although the odds of unbelted drivers being among those killed is more than five times higher than for those who wore seat belts. The odds of female drivers being among the fatalities are 1.28 times higher than those of male drivers, the study indicated.