The difference in mortality rates could also be a result of broad demographic factors in professional sports. Across the U.S. population, for example, white males tend to live about six years longer than black males, a gap that is mitigated—but not eliminated—among paid athletes. A team of researchers in the United Kingdom compared mortality rates among white and black NBA players who were active between 1946 and 2005. Overall, these athletes outlived nonathletes by about 4.5 years, but the white players lived about 1.5 years longer than their black teammates. That disparity persists even in the absence of any major wage discrimination between the two groups.
But if race were the key factor, then Barnwell's findings about baseball and football should have been reversed. According to the Institute for Diversity and Ethics in Sport, 67 percent of NFL players are black and 31 percent are white, compared with 9 percent and 61 percent in baseball. Add in the fact that the NFL is just 1 percent Latino, compared with 27 percent in MLB, and the bias should be even more pronounced, since Hispanic males tend to live longer than either non-Hispanic blacks or non-Hispanic whites. If the longevity of athletes were based entirely on their race, baseball players would have the longest life spans by far, and basketball players the shortest.
Other socioeconomic factors could be at play. For a 2007 paper in the journal Death Studies, a pair of economists in Shippensburg, Pa., examined the longevity of MLB players of the baby-boomer generation. As a rule, the athletes in the study lived longer than equivalent nonathletes, but their life spans were strongly dependent on their level of education. Baseball players who skipped college had twice the risk of death as those who attended a four-year university.
Comparing one sport to another, football players do tend to have more education than baseball players, but the difference is not so dramatic. Among MLB draftees, between 35 and 56 percent are selected right out of high school with no baccalaureate training at all. Meanwhile, about half of the players in the NFL arrive having completed their undergraduate degrees.
Finally, there are dozens, if not hundreds or thousands, of other factors that could explain Barnwell’s results. Consider that Barnwell is comparing players from a certain time period rather than athletes of a certain age. As a consequence, you might expect more MLBers from that time period to have died given that pro baseball players are, on average, older than NFL players. Each sport is also likely to have different training regimens, different rates of anabolic steroid use, and different post-retirement health care options. (Barnwell points to evidence that ex-NFL players are especially likely to have insurance.)
Whatever the explanation, studies like this one tell us nothing about the specific impact of head injuries or whether these sports are dangerous in absolute terms. Nor do they get at the bigger issue that underlies all of the hand-wringing about concussions and players leading with the helmet. Is professional football, or indeed any other sport, simply too dangerous for the athletes involved? If the NFL doesn’t do more to protect its players, should we give up watching in protest?
The exact, long-term effects of head trauma are still unknown, with mixed evidence on whether football players are more likely to develop the symptoms of Parkinson's disease, Alzheimer's disease, and dementia. The original NIOSH study broke down individual causes of death for ex-NFL players, but the sample wasn't big enough to determine whether they were at increased risk of dying from neurodegenerative disease. Taken in aggregate, however, the government data offer some degree of comfort. Considering all the many dangers of the game, a man who takes a job in the NFL has a good chance of living a longer life as a result. That may be apples-to-oranges, as Barnwell points out. But for fans, it's the stat that counts the most.