Vermeer, H.J. and Van IJzendoorn, M.H (2006)
Children’s Elevated Cortisol Levels at Daycare: A review and meta-analysis
Early Childhood Research Quarterly 21, 390-401

  • This paper summarises nine independent studies of the effect of daycare on levels of the stress hormone cortisol in young children.
  • Under normal circumstances, with low stress, all humans including young children will secrete cortisol in a regular pattern: the highest levels in early morning and a gradual decrease during the day.
  • Increases in cortisol secretion and changes to this pattern have been associated with raised levels of stress.
  • Combining all nine studies showed a small but noticeable increase in cortisol levels in children in daycare compared to those cared for in the family home.
  • The differences in cortisol level were higher in the youngest children, particularly two-year-olds, and lower in older pre-school children.