Can you do anything to make your child smarter -- before he or
Can you do anything to make your child smarter -- before he or she is born? Some say it's possible. Here's why they think so.
Nature Versus Nurture
Remember the old "nature versus nurture" debate from biology class? In a nutshell, we're stuck with whatever talents nature gives us, but our environment can nurture -- or hinder -- those gifts.
How important is heredity to intellect?
"Intelligence emerges from the interaction of a person's genetic makeup and the environment in which they develop," Thomas J. Darvill, PhD, tells WebMD. "We have little control over nature's contribution, but the uterine environment is of critical importance and often overlooked by new parents."
Prospective parents with a family history of genetic diseases may benefit from screening and counseling, says Darvill, chairman of psychology and associate director of the Center for Neurobehavioral Effects of Environmental Toxics at Oswego State University in New York.
Biological signs of intelligence suggest, but don't prove, that heredity is an important determinant of IQ, explains Linda Gottfredson, PhD, a professor of education at University of Delaware in Newark.
When it comes to the biological basis of intelligence, size and speed matter. Larger hat size is loosely linked to IQ, although the largest human brain on record belonged to someone with severe mental retardation. Faster reaction time, impulse transmission in nerves, and response of brain waves to unusual sounds are all linked to higher intelligence.
Research by Richard Plomin, PhD, at the Institute of Psychiatry at King's College in London, has identified specific genes predicting high intelligence, reading disability, and mental retardation.
The extent to which genetics accounts for differences in IQ increases with age from about 40% in the preschool years to about 80% in adulthood. "To increase the chances of having a smart baby, marry someone smart!" Gottfredson says.
First, Do No Harm
Perhaps the best practical advice for how to have a smarter baby is not to hinder nature's miracle-in-progress. Even before conception, the mother and probably the father should avoid drugs, alcohol, tobacco, and caffeine, says Stephen J. Schoenthaler, PhD, a professor of nutrition and behavior at California State University in Long Beach.
"Most devastating developmental conditions result from prenatal damage," Darvill says. "If Mom drinks alcohol or uses other recreational drugs, she should stop."
Brain cells depend on chemical signals to tell them where to go, how to connect, and which genes to turn on or off. "Any foreign substance that interferes with the clear transmission of these chemical messages can impact negatively on development," says Darvill.
"Any kind of drug use -- running the gamut from caffeine to heroin -- has the potential to limit the later intellectual development of the unborn child," Shawn K. Acheson, PhD, tells WebMD.
While the evidence is most clear-cut for alcohol, pregnant women should avoid all drugs, says Acheson, an assistant professor of psychology at Western Carolina University in Cullowhee, N.C.
"It's commonsense stuff, but I still see incredibly intelligent pregnant women who should know better continuing to smoke," she says.
Potential Dangers
Less obvious enemies can be equally deadly to the developing brain. One of these is lead from old paint and plumbing. Families living in older homes should have their air and water tested, Darvill says.
Seafood from contaminated waters may harbor brain toxins such as PCBs, methyl mercury, lead, cadmium, and pesticides. Warnings by authorities against eating local fish should be taken seriously by pregnant women, says Philippe Grandjean, MD, professor of environmental health at Boston University School of Public Health. The FDA says moms-to-be should avoid swordfish, king mackerel, tilefish, and other large ocean fish that tend to concentrate toxic chemicals.
Especially during the first trimester, infections like German measles or toxoplasmosis, which is caused by a parasite that can be contracted through contact with infected cat feces, can wreak havoc on the embryonic brain. So pregnant women should stay away from sick children and avoid changing the litter box whenever possible.
Thyroid disease is another culprit that can sneak up unnoticed, says endocrinologist John Lazarus, MD. Babies born to women with low thyroid function are more likely to have low IQ. To determine whether thyroid replacement in similar women might help, his group at the University of Wales College of Medicine in Cardiff has started a seven-year clinical study.
