A study reveals ancient human teeth showing evidence that stressful events during early development are linked to shorter lifespans.
Anthropologist George Armelagos led a systematic review of defects in teeth enamel and early mortality.
He said: ‘Prehistoric remains are providing strong, physical evidence that people who acquired tooth enamel defects while in the womb or early childhood tended to die earlier.
‘During prehistory, the stresses of infectious disease, poor nutrition and psychological trauma were likely extreme. The teeth show the impact.’
His paper is the first summary of prehistoric evidence for the Barker hypothesis – the idea that many adult diseases originate during foetal development and early childhood.
He added: ‘Teeth are like a snapshot into the past. Since the chronology of enamel development is well known, it’s possible to determine the age at which a physiological disruption occurred. The evidence is there, and it’s indisputable.’
The Barker hypothesis is named after epidemiologist David Barker, who during the 1980s began studying links between early infant health and later adult health.
Tooth enamel can give a particularly telling portrait of physiological events, since the enamel is secreted in a regular, ring-like fashion, starting from the second trimester of foetal development.
Disruptions in the formation of the enamel, which can be caused by disease, poor diet or psychological stress, show up as grooves on the tooth surface.
Armelagos and other bio-archaeologists have noted the connection between dental enamel and early mortality for years.
For the Evolutionary Biology paper, Armelagos led a review of the evidence from eight published studies, applying the lens of the Barker hypothesis to remains dating back as far as one million years.
One study of a group of Australopithecines from the South African Pleistocence showed a nearly 12-year decrease in mean life expectancy associated with early enamel defects.
In another striking example, remains from Dickson Mounds, Illinois, showed that individuals with teeth marked by early life stress lived 15.4 years fewer than those without the defects, says an EU release.
The findings were published in Evolutionary Anthropology.