Family conflict slows children's growth and has potential long- term consequences for their health and well-being, scientists say.
A study of 6,500 children born in the same week found that almost 300 - 4.5 per cent - had experienced conflict as a result of domestic tension, divorce, separation or desertion, as judged by a health visitor. On average, at age seven, they were 10 centimetres shorter than the other children.
Previous studies have shown that men who were short as children are more likely to be unemployed as adults, whatever their education and background. One study showed that among the tallest 20 per cent at age seven, 8 per cent were unemployed while among the shortest 20 per cent, 20 per cent were unemployed.
Height at age seven is a better predictor of adult unemployment than adult height. The reason is thought to be that slow growth may not itself be a disadvantage but is an indicator of damaging influences on cognitive and psychological development in childhood which has long-term consequences.
Dr Scott Montgomery, chief author of the study published in Archives of Disease in Childhood, said: ``Stress in childhood begins a cycle of disadvantage and at every stage throughout their lives, these children accumulate health risks. Short men die younger and suffer more sickness.''
Dr Montgomery, of the department of medicine at the Royal Free Hospital, London, said acute stress stimulated production of human growth hormone which controls metabolism and is important in the ``fight or flight'' response, as well as being essential for growth. Chronic stress, however, dulls the response by increasing levels of beta-endorphin, a brain chemical which reduces the amount of growth hormone released. Gluco-corticoid levels are also increased which interferes with the development of the hippcampus, the area of the brain that deals with learning and memory.
Experiments with rats subjected to stress showed they could not learn the route through a maze as well as those that were not stressed..
The study also showed that children from the most crowded households were three times more likely to be short for their age as those from the least crowded homes. The researchers say this may be because overcrowding is associated with poverty, which is linked with poorer health, or because it disrupts sleep, when growth hormone is released.Reuse content