Is the US Old-Age Mortality Advantage Vanishing?¹

Americans experience higher mortality than their peers in other high-income countries for most of the life course, but recent work has shown that at the oldest ages they experience a mortality advantage- a phenomenon we call the "US mortality crossover." In this paper we document the crossover and time trends thereof. We find that the age of crossover increases linearly by about 0.5 years per year, a pattern of changes that, to our knowledge, has not been identified before. We then interrogate several potential explanations for a steadily increasing crossover age. While none is completely satisfactory, we rule out differential age misstatement, selection, and access to and quality of health care. We find that the most plausible explanations involve the deleterious effects of differential smoking and obesity but we are unable to adjudicate more precisely if either of these independently or in combination explain the phenomenon.