Children's Height and Intelligence Linked
The results: The shorter the child's height at age 5, the poorer he or she performed on the test at age 10, no matter the child's birth weight or family income. The implication is that slower childhood growth is associated with lower intelligence.
Why? It could be that environmental factors, such as a stressful home life, have a negative effect on both early childhood growth and mental development. "Childhood stress can slow growth significantly," lead study author Dr. Scott Montgomery told Reuters Health. There is evidence that long-term stress, such as that caused when parents argue frequently or divorce, can cause a child's growth to be impaired by affecting the body's production of a growth hormone. Some children--and by no means all--are shorter than they should be because of this. At the same time, such stress can influence the development of brain regions that are involved in memory and learning, according to Montgomery.
The opposite is also true. "A happy childhood is likely to enhance both physical growth and intellectual growth," he told Reuters.
IMPORTANT: Many children are shorter than average because that is their genetic makeup, and this is not due to an underlying environmental problem, such as family stress. In this case, short stature will not negatively influence their intelligence or performance on IQ tests.
The study findings were published in the Archives of Disease in Childhood.