Scientists suggest they have found a reason why some shorter children perform less well at school. A Children of the 90s study by the University of Bristol found low growth hormone levels were linked to low IQ. The Pediatrics study suggests it would be possible to use diet to increase levels of the hormone. But other experts said, even if growth hormone levels did play a role, it would be a tiny part of the “jigsaw” of factors which affect development. It is already known that low birth weight babies develop more slowly, reaching development milestones later and having slightly lower IQs than normal weight babies. Short stature, linked to poor post-natal growth and nutrition, is also known to be related to poorer performance in intellectual development tests and in educational achievement. The Bristol team looked at what might happen in the body to explain these links, focusing on insulin growth factor (IGF-I) . Circulating levels of insulin-like growth factors are influenced by a variety of factors, including diet, and control the effects of growth hormone on tissues. IGFs play a key role in physical growth and organ development in childhood. It has been suggested that they could also affect the development of the brain.
