The evidence doesn't support the theory

EDITOR,—David Barker and colleagues suggest that suicide in adulthood may be a direct consequence of low weight during the first year of life.1 This deterministic theory of development is based on the idea of fetal programming of neuroendocrine function, which is a common cause of poor weight gain in infancy and of depression, leading to suicide, in later life. This is in contrast with modern studies of psychosocial risk, which suggest that development is a non-linear, probabilistic process—and is not based on linear, deterministic principles.2

The evidence presented in the …