Researchers at the Royal Free Hospital School of Medicine in London followed 6,574 children born in 1958 for several decades. One of their findings: At age 7, the children from troubled homes were almost twice as likely to be of short stature as those from more peaceful homes. These kids also tended to be underachievers at school.
Scott Montgomery, M.D., lead researcher of the study, and his colleagues think that chronic stress may both inhibit the production of growth hormones and increase the secretion of so-called stress hormones. One of the most important of these, cortisol, influences the functioning of the hippocampus, the part of the brain that controls learning and memory.
Montgomery points out that while many of the children he studied later caught up to their peers in height, "cognitive development could be permanently impaired" by living in an environment of ongoing conflict.