Utilizing the 'Metropolitan' database, which provides unique longitudinal d
ata on a cohort of 15,000 individuals born in Stockholm in 1953, the paper
tests various hypotheses on how conditions in childhood and social upbringi
ng influence sickness absence in adulthood. The hypotheses were derived fro
m different perspectives within the social sciences. The findings suggest t
hat the effects of social background are transmitted via several mechanisms
, and that it is useful to see some of the competing hypotheses on social c
lass and health-related phenomena as complementary rather than contradictor
y. However, the results also suggest that both 'the culture of poverty hypo
thesis' and the 'biological imprint hypothesis' should be rejected. Because
effects of social background are mediated by career variables such as scho
ol performance, educational level and current socio-economic status, the re
sults support the 'unfavourable life career hypothesis'. In addition to the
se effects, an influence of being brought up in a family with serious domes
tic problems is found, This is congruent with 'the social imprint hypothesi
s', that childhood conditions may have lasting effects on conditions and be
haviours in adult life, irrespective of later exposure.